An international research team, which included scientists from the Faculty of Science at Palacký University and the Institute of Physics of the Czech Academy of Sciences, has succeeded in unraveling the complex mechanism by which a chemical bond is formed during a collision between molecules. The experts found that the reaction only takes place if the molecules are oriented towards each other within a very narrow range of angles – within the so-called cone of reaction. This joint research has thus provided an answer to one of the fundamental questions of chemistry: under what conditions do chemical bonds form between molecules. The results of the study&nbsp;Spatially resolving the cone of reaction for a single molecule&nbsp;were published in the prestigious scientific journal&nbsp;Science.Many chemical reactions begin with the collision of two particles. However, for a new chemical bond to form, it is not enough for the molecules simply to come into contact. Their collision must occur with sufficient energy, in the correct relative orientation and at the right location. Under normal conditions, such as in solutions or gases, molecules collide chaotically, and the precise parameters of these collisions cannot therefore be controlled.<h4>Molecules under control</h4>Scientists were able to control the collisions of individual molecules on a copper surface and monitored the process using a scanning tunnelling microscope. They used the instrument not only to visualise individual molecules, but also to deliberately accelerate the reactants towards one another. They subsequently analysed each collision with atomic-level resolution. This enabled them to determine unequivocally whether a new chemical bond had formed between the molecules.<h5>“What is hidden in the statistics of billions of collisions in conventional chemistry, we have managed to break down into individual cases and map directly.” Adam Matěj</h5>A key finding of the study is that the outcome of a collision is determined by the extremely precise orientation of the molecules. A new bond was formed only when the target molecule was oriented within a few degrees of the direction of movement of the other molecule. When rotated by more than fifteen degrees, the molecules simply bounced off each other without any reaction.<h4>The precise orientation of the molecules is crucial</h4>“For the first time, we were able to observe, using a single molecule, exactly how precisely it must be oriented for the reaction to take place at all. What is hidden in the statistics of billions of collisions in conventional chemistry, we have managed to break down into individual cases and map directly,” said Adam Matěj from the Department of Physical Chemistry at the Faculty of Science.The theoretical part of the study, in which researchers from Palacký University and the Institute of Physics of the Czech Academy of Sciences were involved, played a significant role. Using quantum-mechanical calculations, they explained why the ‘reaction cone’ is so narrow. It turned out that the reactive carbon atom is surrounded by hydrogen atoms, which block the access of the reacting molecule from almost all directions.<h4>The arrangement of atoms restricts access to the reaction</h4>The calculations also shed light on a surprising experimental result. The chemical reaction took place even when the molecule moved along an adjacent row of copper atoms, where, according to the original assumptions, no bond should have formed.<h5>“The strength of this work lies in the fact that the experiment and theory have been brought together into a single picture. The microscope showed what happens during the collision, and the calculations explained why.” Pavel Jelínek</h5>“The explanation lies in the slight displacement of a single copper atom on the surface. The target’s bond to the surface pulls it out of its position and brings it close enough to the neighbouring row that it can literally take over the projectile and direct it to the correct spot. This shows that the surface is not merely a passive substrate, but actively participates in the reaction itself and can even facilitate pathways that would otherwise be unfavourable,” noted Adam Matěj.<h4>The surface also determines the course of the reaction</h4>The results are significant for the development of so-called surface reactions, in which new materials and nanostructures are purposefully assembled from individual molecules. A better understanding of the influence of the spatial arrangement of molecules will enable the design of molecular building blocks so that they bond more reliably and efficiently. This represents an important step towards the development of technologies based on the controlled construction of structures atom by atom.“The strength of this work lies in the fact that experiment and theory have been brought together into a single picture. The microscope showed what happens during the collision, and the calculations explained why. Without a theoretical model, we would have found it difficult to discover that the movement of a single surface atom is behind the unexpected course of the reaction,” added Pavel Jelínek from the Institute of Physics of the Czech Academy of Sciences.<blockquote>The study&nbsp;Spatially resolving the cone of reaction for a single molecule&nbsp;was produced in collaboration between researchers from the University of Graz, the Institute of Physics of the Czech Academy of Sciences, Palacký University in Olomouc, Charles University and Humboldt University in Berlin.</blockquote>

Scientists reveal when chemical bonds form in molecular collisions 

In our <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/article/7741">previous article, we introduced the main types of detectors used in HPLC</a>. This time, we take a closer look at the performance characteristics of LC detectors and the specifications that should be considered when assessing whether a detector is suitable for a particular chromatographic separation. We will also compare the most common detector technologies and provide some practical guidance for choosing the right option for a specific application.<h3>What Defines an Ideal HPLC Detector?</h3>With such a wide variety of HPLC detectors available, an obvious question arises: why is there no single detector that works for every application? The simple answer is that no detector can satisfy every analytical requirement at the same time. Nevertheless, most detector designs aim to achieve a similar set of desirable properties.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Figure_1_Detector_requirements_334605c913.webp" alt="KNAUER: Figure 1 - Detector requirements" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Figure_1_Detector_requirements_334605c913.webp 245w," sizes="100vw" width="1024" height="384"><h4>1. High Sensitivity – Detecting Very Small Amounts</h4>An ideal detector should be capable of measuring very low quantities of analyte, often in the nanogram or even picogram range. High sensitivity leads to lower limits of detection (LOD), can reduce sample preparation requirements, and is particularly valuable for applications such as impurity analysis or pharmacokinetic studies.Some detector technologies, including fluorescence detection (FLD), electrochemical detection (ECD), and mass spectrometry (MS), can achieve extremely high sensitivity. However, this level of performance is often limited to specific classes of compounds.<h4>2. Good Selectivity or Broad Applicability – Knowing What Is Being Detected</h4>Selectivity describes how effectively a detector responds to the target analyte while minimizing interference from the sample matrix or mobile phase.Depending on the analytical task, a detector may need to be highly selective, responding only to compounds with specific characteristics such as fluorescence or electrochemical activity. In other cases, broader applicability may be more important, allowing a wide range of compounds to be detected regardless of their molecular structure.<h4>3. Linear Response and Broad Dynamic Range – Reliable Quantification</h4>A good detector should provide a linear response across a sufficiently wide concentration range. This makes it possible to accurately quantify both major components and trace impurities within the same analytical method.A broad linear range simplifies calibration and improves confidence in quantitative results. Detector response should also remain highly reproducible from one injection to another.<h4>4. Compatibility with HPLC Conditions – Fitting the Chromatographic Method</h4>An ideal detector should be compatible with both gradient and isocratic elution, commonly used mobile phases and additives, typical flow rates, and standard HPLC operating temperatures.Poor compatibility may restrict method flexibility or force compromises in chromatographic performance. Some detectors provide excellent analytical performance but only under specific operating conditions, making them less suitable for certain methods.<h4>5. Stability and Low Noise – Distinguishing Signal from Background</h4>A stable baseline with minimal noise and drift improves the signal-to-noise ratio and overall data quality. This becomes especially important in long chromatographic runs, gradient methods, and trace-level analysis.Lower baseline noise makes weak analyte signals easier to distinguish and directly contributes to improved detection limits.<h4>6. Robustness, Ease of Use, and Maintenance – Supporting Routine Laboratory Work</h4>For day-to-day use, a detector should be reliable over long sequences, straightforward to operate, and require as little maintenance as possible.In routine laboratories, robustness and ease of operation can be just as important as analytical performance. Simple troubleshooting, low maintenance requirements, and limited consumable costs are major advantages, particularly in high-throughput environments.<h3>The Reality: No Detector Offers Everything</h3>Since no detector fulfils all these requirements perfectly, detector selection is inevitably a compromise between sensitivity, selectivity, universality, robustness, operating flexibility, and cost.For this reason, multi-detector configurations are increasingly common in modern HPLC systems. Combinations such as UV + CAD or UV + MS make it possible to benefit from complementary detection principles within a single analytical workflow.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Table_1_Comparison_of_commonly_used_HPLC_detector_classes_d74817b0f0.jpg" alt="KNAUER: Table 1 - Comparison of commonly used HPLC detector classes." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Table_1_Comparison_of_commonly_used_HPLC_detector_classes_d74817b0f0.jpg 113w," sizes="100vw" width="806" height="1115"><h3>Critical Performance Parameters of HPLC Detectors</h3><h4>Data Sampling Rate</h4><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Figure_2_Example_for_too_less_and_too_high_data_sampling_rate_741a53edc6.webp" alt="KNAUER: Figure 2 - Example for too less and too high data sampling rate." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Figure_2_Example_for_too_less_and_too_high_data_sampling_rate_741a53edc6.webp 245w," sizes="100vw" width="1024" height="410">The data acquisition rate, also known as the sampling rate, is one of the most important detector settings in HPLC. It describes how many data points are recorded per second and directly influences peak representation, peak shape, area precision, and baseline noise.The higher the sampling rate, the more data points are collected. The detector processes the measurements collected over a defined time interval and averages them, and these averaged points are then used to construct the chromatogram.At a data rate of 5 Hz, for example, five data points are acquired every second. If too few points are collected across a chromatographic peak, the resulting peak can appear jagged, poorly defined, and analytically unreliable, as illustrated on the left side of Figure 2.At the other extreme, a setting such as 100 Hz records 100 points each second, which is often unnecessarily high for conventional HPLC. The optimum sampling rate mainly depends on chromatographic peak width.For most standard HPLC applications, a data rate of approximately 10 to 20 Hz is sufficient to generate a smooth and symmetrical Gaussian peak.One consequence of using an excessively high acquisition rate is increased baseline noise. Statistically, the noise of the system depends on the number of data points used for averaging and decreases with the square root of the number of averaged measurements.Selecting an appropriate sampling rate is therefore a balance between collecting enough points to describe the chromatographic peak accurately and avoiding unnecessary noise.<h4>Noise and Drift</h4><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Figure_3_Baseline_noise_and_drift_685652e641.webp" alt="KNAUER: Figure 3 - Baseline noise and drift" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Figure_3_Baseline_noise_and_drift_685652e641.webp 245w," sizes="100vw" width="1024" height="400">What exactly is baseline noise? In simple terms, it represents the short-term fluctuations of the detector baseline over a defined period and is expressed in the units appropriate for the particular detector.Baseline noise is typically determined from the peak-to-peak variation of the detector signal while the mobile phase passes through the system.All HPLC detectors exhibit a certain level of noise. Potential sources include:<ul><li>electronic noise,</li><li>detector cell noise,</li><li>detector instability,</li><li>temperature fluctuations,</li><li>mobile-phase effects,</li><li>and other environmental or instrumental influences.</li></ul>Noise directly affects detector sensitivity because it determines the signal-to-noise ratio (S/N).A chromatographic peak is generally considered reliably detectable when its height is at least three times greater than the calculated baseline noise. This relationship is commonly used to define the limit of detection (LOD).The limit of quantification (LOQ) requires a stronger signal and is typically defined as approximately ten times the baseline noise.Another important parameter affecting sensitivity is baseline drift. Drift reflects the gradual change in detector response over time and therefore provides useful information about long-term detector stability.It is helpful to distinguish between short-term peak-to-peak noise and longer-term baseline drift over a defined time interval. Drift can be described as the average slope or change of the baseline within a specific period.Excessive drift may reduce sensitivity and complicate chromatographic peak integration.Short-term baseline instability can be influenced by contamination or deterioration of detector components, while long-term drift is often related to temperature stability, detector equilibration, or changes occurring within the analytical system.<h3>How to Select the Right HPLC Detector</h3>There is no universally “best” HPLC detector. The correct detector is simply the one that best matches the analytical task.When selecting a detector, several practical questions can help narrow the choice.<h4>1. Does the analyte absorb UV light or fluoresce?</h4>If the answer is yes, optical detectors such as UV/VIS or FLD are often the simplest and most effective options.UV/VIS detection is widely applicable to compounds containing suitable chromophores, while fluorescence detection provides particularly high sensitivity and selectivity for naturally fluorescent or derivatized analytes.<h4>2. Does the analyte lack a chromophore?</h4>If UV absorption is weak or absent, detectors such as RID, ELSD, or CAD may provide a more appropriate solution.These detector types are useful for compounds such as sugars, lipids, polymers, and other analytes that are difficult to monitor by conventional UV detection.<h4>3. Is structural information required?</h4>If structural information is important, mass spectrometry is usually the strongest choice.MS provides mass-to-charge information and, when tandem mass spectrometry is used, fragmentation data that can support compound identification and structural characterization.<h4>4. Is extremely high sensitivity necessary?</h4>For applications requiring very low detection limits, electrochemical detection or mass spectrometry may be the most suitable options.The exact choice depends on the chemical properties of the analyte and the required degree of selectivity.<h4>5. Are macromolecules such as proteins or polymers being investigated?</h4>For characterization of macromolecules, MALS and viscometry can provide valuable information about molecular weight, molecular size, branching, and aggregation.These techniques are especially powerful when combined with size-exclusion chromatography and can provide information that is not based solely on column elution behavior.For a more detailed discussion of detector selection, see the KNAUER blog article “The way you look at it – A comprehensive guide for selecting the appropriate HPLC detector.”Choosing the detection technology based on analyte properties, required sensitivity, chromatographic conditions, and the type of information needed is essential for obtaining reliable and meaningful HPLC results.<h3>Final Thoughts</h3>Understanding the desired characteristics and key performance parameters of HPLC detectors helps explain why different detector technologies are suited to different applications.No single detector can provide maximum sensitivity, selectivity, universality, robustness, flexibility, and low operating cost simultaneously. Recognizing these trade-offs provides a practical framework for selecting the most appropriate detector for a given chromatographic method.Parameters such as data sampling rate, baseline noise, drift, dynamic range, and compatibility with chromatographic conditions are just as important as the underlying detection principle itself.In the next articles of this series, we will take a closer look at the individual HPLC detection technologies, beginning with the most widely used optical detection method: UV/VIS detection.

Seeing is Believing – Detection Made Easy Part 2: Detector Characteristics

Our Library never stops expanding. What are the most recent contributions to LabRulezLCMS Library in the week of 17th August 2026? Check out new documents from the field of liquid phase, especially HPLC and LC/MS techniques!<blockquote>👉 <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library">SEARCH THE LARGEST REPOSITORY OF DOCUMENTS ABOUT LCMS AND RELATED TECHNIQUES</a></blockquote><blockquote>👉 Need info about different analytical techniques? Peek into <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library">LabRulezGCMS</a> or <a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/library">LabRulezICPMS</a> libraries.</blockquote>This week we bring you posters by Agilent Technologies / ASMS, Thermo Fisher Scientific / ASMS and Shimadzu / ASMS and application note by Waters Corporation!<h3>1. Agilent Technologies / ASMS: Quantitation of N-Nitroso Duloxetine N-Nitrosamine Drug Substance Related Impurities (NDSRI) in API and Formulation by 6475 LC/TQ</h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/po_drug_impurities_lc_tq_tp_402_asms_2026_en_agilent_b933b9bddf.pdf">Full PDF for download</a></li></ul>Nitrosamine impurities are nitroso derivatives where the nitroso group is attached to an amine. The active pharmaceutical ingredient (API) derived from a class of nitrosamines are known as N-nitrosamine drugsubstance-related impurities (NDSRI). Nitrosamine impurities in APIs and drug products pose safety concerns, even in small quantities, and thus are a major concern for drug makers [1].&nbsp;Analytical methods must be sufficiently sensitive to quantify the nitrosamine of interest at levels as low as 10% of the specification limit and, where feasible, down to ≤5% of the specification limit, for the determination of the limit of detection. LC/MS/MS is an inherently selective and highly sensitive analytical technique that is well suited for the identification and quantification of trace-level impurities at extremely low concentrations. Consequently, LC/MS/MS has been widely adopted within the pharmaceutical industry, particularly for nitrosamine analysis [2-3].&nbsp;Therefore, manufacturers must develop and qualify a dedicated analytical method that is appropriate for the specific sample matrix and targeted NDSRIs. An LC/MS/MS method based on multiple reaction monitoring (MRM) was developed for the detection and quantification of the N-nitroso duloxetine NDSRI impurity over a concentration range of 0.5 to 40 ppb (absolute standard concentration), using an atmospheric pressure chemical ionization (APCI) source on an Agilent 6475A LC/TQ instrument.<h4>Experimental</h4><ul><li>MS: <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?mainauthorItems=10&amp;search=6475">6475 Triple Quadrupole LC/MS System</a></li><li>Column: <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?mainauthorItems=10&amp;search=Poroshell+HPH+C18">Poroshell HPH C18</a> (4.6*150mm, 2.7µm)</li></ul><h4>Conclusions</h4><ul><li>A highly sensitive and robust MRM LC/MS/MS method was developed for the quantitation of N-nitroso duloxetine in duloxetine hydrochloride API and finished formulation using the Agilent 6475A LC/TQ.&nbsp;</li><li>The optimized chromatographic conditions provided effective separation of the analyte from the API, placebo, and formulation matrices, ensuring reliable quantitation.&nbsp;</li><li>The calibration curve was linear over the concentration range of 0.5-40 ng/mL, with 1/x weighting. R and R2 values were observed for both to be greater than 0.99.&nbsp;</li><li>Recovery studies demonstrated efficient sample extraction, with recoveries ranging from 92-99% in API samples and 109-116% in pellet formulations at the LOQ, specification, and 200% specification levels.&nbsp;</li><li>The method also showed excellent reproducibility across all evaluated concentration levels, confirming its suitability for routine analysis.</li></ul><h3>2. Shimadzu / ASMS: Non-Targeted Analysis of Per- and Polyfluoroalkyl Substances in Environmental Extracts by Microflow LC-QToF Coupled with Multi-spray ESI</h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/TP_562_Non_Targeted_Analysis_of_Per_and_Polyfluoroalkyl_Substances_in_Environmental_Extracts_by_Microflow_LC_Q_To_F_Coupled_with_Multi_spray_ESI_c2a7e1d5bf.pdf">Full PDF for download</a></li></ul>Targeted screening methods are well established for monitoring Perand polyfluoroalkyl substances (PFAS) in environmental samples. However, PFAS comprise a large and evolving class of compounds, creating a need to screen existing, emerging, and transformation products across diverse matrices. Non-targeted Analysis (NTA) allows for the confirmation of suspected PFAS in the environment, but the sample characterization is often limited by analytical sensitivity. Microflow (0.5 – 40 µL/min) coupled with a multi-nozzle emitter enhances sensitivity by improving desolvation. When this is coupled to a high mass accuracy and resolution Quadrupole Time-ofFlight Mass Spectrometer (QToF), capable of data-dependent and independent MS/MS, PFAS characterization of unknown analytes is possible. In this study, various environmental extracts were processed and screened using NTA for PFAS compounds.<h4>Methods</h4>A <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?mainauthorItems=1&amp;search=Nexera+Mikros">Shimadzu Nexera Mikros LC </a>was used to introduce the sample to a Newomics DuoESI source with an M3 emitter on a <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?mainauthorItems=1&amp;search=9050">LCMS-9050 QToF MS</a> (Fig. 1). A direct injection on an octadecyl column without delay column was performed. Direct injection was chosen over trapand-elute configuration to minimize selectivity bias caused by the trap column.&nbsp;<h4>Conclusion</h4>With the increased sensitivity of microflow LC-QToF coupled with multi-spray ESI with DIA acquisition, Insight Explore aided in NTA PFAS analysis. When paired with Insight Discovery and Profiler, a streamlined batch data processing workflow with statistical analysis was shown to effectively handle complex environmental matrices and their analyses.<h3>3. Thermo Fisher Scientific / ASMS: Robust and sensitive quantitation of 18 steroids in human serum using Thermo Scientific TSQ Certis Triple Quadrupole mass spectrometer</h3><ul><li>Poster</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/po_004707_lsms_18_steroids_tsq_certis_clinical_po004707_asms2026_na_en_244c52437b.pdf">Full PDF for download</a></li></ul>Accurate quantification of endogenous steroids in human serum is essential for biomonitoring physiological functions such as hormone regulation, reproduction, and immune response in clinical research laboratories. Liquid chromatography–tandem mass spectrometry (LC–MS/MS) is the gold standard for steroid analysis due to its superior sensitivity, selectivity, and multiplexing capability compared to immunoassays. However, steroid measurements remain challenging because of low endogenous concentrations and complex serum matrices. Here, we describe a robust and sensitive LC–MS/MS method for the simultaneous quantification of 18 steroids in human serum using the Thermo Scientific TSQ Certis triple quadrupole mass spectrometer (Figure 1). The method leverages advanced ion source design and fast acquisition to deliver enhanced sensitivity, stability and throughput suitable for high-volume laboratory workflows.<h4>Materials and methods</h4><h5>Liquid chromatograph – mass spectrometry&nbsp;</h5>Samples were analyzed on a <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/744">Thermo Scientific Vanquish Horizon UHPLC system</a> coupled to the <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2207">TSQ Certis MS</a> operated in selected reaction monitoring (SRM) mode. The mobile phase composition, analytical column details, LC gradient, and overlaid extracted ion chromatograms (EICs) are shown in Figure 3.&nbsp;<h5>Data analysis&nbsp;</h5>Data were acquired and processed using <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/77">Thermo Scientific TraceFinder software</a> (v 5.2).<h4>Conclusions&nbsp;</h4>A sensitive and robust LC–MS/MS method was developed for simultaneous quantification of 18 steroids in human serum using the Vanquish Horizon UHPLC and TSQ Certis MS with OptaMax Plus ion source. The method demonstrated excellent linearity, accuracy, and reproducibility across a wide dynamic range. Optimization of MS conditions, particularly vaporizer temperature, significantly improved sensitivity. Overall, the workflow delivers high sensitivity, selectivity, and long-term stability, providing a reliable solution for high-throughput steroid analysis in clinical and research settings.<h3>4. Waters Corporation: Alkaline-hydrolysis Method for PFAS in Textiles and Textiles Products by Xevo™ TQ-S micro with ACQUITY™ UPLC™ H-Class Plus System</h3><ul><li>Application note</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/720009443_en_0ab4914d72.pdf">Full PDF for download</a></li></ul><div><div><section><div><div><div><div><div><div><h5>Benefits&nbsp;</h5><ul><li>Alkaline hydrolysis method (EN 17681-1:2025) used for preparing textiles, coated textiles and textile products for PFAS analysis allowed the inclusion of side-chain fluorinated polymers&nbsp;</li><li>Extraction method provided significant advantages in handling complex textile matrices by creating clear extracts free from dispersions, settleable solids and particulates&nbsp;</li><li>Protected the high-value LC-MS/MS components from potential damage&nbsp;</li><li>The method improved analytical sensitivity, reproducibility and accuracy, enabled cost-effective and timeefficient PFAS analysis maintained high analytical quality even for challenging high-matrix samples</li></ul>Many PFAS are linked to health concerns because of their ability to interfere with the body’s hormone systems, acting as endocrine disruptors also, linked to other toxic effects. Since textiles come into direct and prolonged contact with the skin, there is an increased risk of human exposure—especially for babies and children.4 In addition, PFAS pose significant environmental concerns. These “forever chemicals” do not readily break down and can be released during manufacturing, washing and disposal, allowing them to enter water pathways and persist in the environment. As a result, testing for PFAS has become increasingly important in the textile industry to demonstrate supply chain transparency, build consumer trust and protect brand reputation.Synthetic fluorinated chemicals are categorized into two main groups - non-polymeric PFAS and polymeric PFAS, known for their use as water and grease repellent, heat resistant finishes in textiles, upholstery, leather, apparel, carpet and other industrial applications such as packaging, firefighting foams, non-stick cookware, etc. (Figure 1). PFAS are fluorinated substances contain at least one fully fluorinated methyl or methylene carbon atom (without any H/Cl/Br/I atom attached to it), i.e. with a few noted exceptions, any chemical with at least a perfluorinated methyl group or a perfluorinated methylene group.2 PFAS are classified as long chain and short chain based on their perfluorinated carbon chain length. Short chain fluorinated polymers encompasses a diverse range of chemistries, categorized according to their generic chemical and repeating units structures. Few examples are: derivatives of fluorotelomers, perfluoropolyethers with varying carbon chain lengths and acrylates, epoxylates, urethane, silicones of repeated units based structures.3 Polyfluoroalkyl substances such as fluorotelomer alcohols (FTOHs) contain C–H bonds, rendering them more susceptible to degradation. The ethoxylates in fluorotelomers-methacrylate break down to FTOH whereas polymeric fluorinated urethanes, acrylates break down to PFCAs (non-polymeric and polymeric side chain fluorinated polymers). In contrast, perfluoroalkyl substances such as PFOS and PFOA are extremely persistent due to their fully fluorinated carbon chains.&nbsp;In alkaline hydrolysis methods, methanolic aqueous sodium hydroxide is used to break down precursor PFAS such as FTOHs, branched side chain PFAS. This process releases terminal perfluorinated carboxylic acids (PFCAs), which can then be measured. However, the efficiency of hydrolysis varies among different PFAS compounds and the presence of interfering substances such as organic matter or other chemicals in the sample matrix can inhibit the cleavage and detection of these analytes.<h4>Experimental</h4><ul><li>LC system: <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/198">ACQUITY UPLC H-Class Plus System</a> and SMFTN fitted with PFAS kit</li><li>Column(s): <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/1823">XBridge™ BEH™ C18 5 µm Column</a>, 4.6 x 100 mm&nbsp;</li><li>MS system: <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/209">Xevo TQ-S micro Mass Spectrometer</a></li></ul><h4>Conclusion&nbsp;</h4>By strictly following the critical steps of the alkaline hydrolysis method using methanolic aqueous sodium hydroxide (NaOH) both freely extractable PFAS and those previously bound within side-chain fluorinated polymers such as esters linked to fluorotelomer alcohols (n:2 FTOHs, where n = 4, 6, 8, 10, 12), can be effectively extracted. This approach also safeguards the LC-MS/MS instrumentation from blockages, damage, or contamination by preventing polymer accumulation and matrix interferences.&nbsp;The analytical method using the ACQUITY UPLC H-Class Plus System and Xevo TQ-S micro LC-MS/MS System was found to be sensitive, reproducible and accurate, enabling cost-effective and time-efficient PFAS analysis in chemically processed textiles, coated textiles and textile products whilst maintaining high analytical quality even for challenging high-matrix samples.</div></div></div></div></div></div></section></div></div>

News from LabRulezLCMS Library - Week 34, 2026

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Everything from the world of analytical chemistry in one place. We connect people in solving their problems. At Labrulez you will find all the necessary information easily, quickly and clearly. Stop searching and start finding.

LabRulez

Based in Berlin, KNAUER is a medium-sized, owner-managed company that has been serving the sciences since 1962. We develop and manufacture scientific instruments of superior quality for liquid chromatography, including: Analytical HPLC/UHPLC, Preparative HPLC, Fast protein liquid chromatography (FPLC), Multi-column chromatography/Simulated moving bed (SMB) chromatography. High pressure dosing, in-line detection systems, and osmometry are additional business areas.

KNAUER

Palacký University Olomouc (UP) is an internationally respected and scientifically and academically highly productive university in Central Europe. Founded 22 December 1573, it is the second-oldest university in the Czech Republic and the oldest one in Moravia. For 450 years it has contributed to the intellectual wealth of society and to its scientific, cultural, and social development.

Palacký University Olomouc

Determination of nitrosamine content (Bioanalytic)

Our offer includes comprehensive development and validation of methods for determination of nitrosamines in pharmaceutical products. We perform the work according to the criteria and needs of the client based on the EMA note.

Determination of nitrosamines is one of the pharmaceutical industry's top priorities. After the presence of N-nitrosodimethylamine (NDMA) was first reported in an active pharmaceutical ingredient (API), the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) mandated the identification and control of all APIs and finished products in which there is a risk of nitrosamines.The content of nitrosamines in drug products can be controlled primarily by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) analysis. More than that, a reliable analysis result in our offer consists of a well-chosen sample preparation procedure, a selective and sensitive analytical method, and the experience of the analyst, who selects the best method parameters at the optimization stage.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Bioanalytic_Determination_of_nitrosamine_content_Bioanalytic_2_ce4f440837.jpg" alt="Bioanalytic: Determination of nitrosamine content." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Bioanalytic_Determination_of_nitrosamine_content_Bioanalytic_2_ce4f440837.jpg 234w," sizes="100vw" width="1536" height="1024">We have gained experience working with leading pharmaceutical companies. As part of our ongoing work, we have developed analytical methods for small-molecule nitrosamines of 70-150 g/mol. These compounds are mainly formed during manufacturing processes and depend on the presence and type of excipients (e.g. NDBA - N-nitroso-dibutylamine). We have also developed methods for determining molecules with higher nitrosamine drug substance related impurities (NDSRIs). In our work, we focus on achieving the highest possible sensitivity, selectivity and precision. To this end, we individually select the parameters of the methods depending on the composition of the drug and the expected nitrosamines. Due to the above criteria and the required detection limits, we perform nitrosamine impurity determinations using LC-MS/MS kits based on <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?manufacturerItems=52&amp;search=QTRAP+5500%2B">QTRAP 5500+</a> and <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?manufacturerItems=52&amp;search=QTRAP+6500%2B">QTRAP 6500+</a> mass spectrometers (<a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?mainauthorItems=55">SCIEX</a>).<blockquote>Our offerOur offer includes comprehensive development and validation of methods for determination of nitrosamines in pharmaceutical products. We perform the work according to the criteria and needs of the client based on the EMA note.At the stage of sample preparation, we focus on:<ul><li>obtaining the highest possible recovery of nitrosamines (matrix purification);</li><li>limiting additional synthesis of impurities (selection of appropriate equipment and reagents);</li><li>ensuring the stability of the sample prepared for LC-MS/MS analysis.</li></ul>During the optimization of the LC-MS/MS method, we solve such problems as:<ul><li>selection of an appropriate internal standard;</li><li>separation of the impurity from the API;</li><li>obtaining the expected sensitivity of the analytical method.</li></ul>Quantitative analysis of nitrosamines requires sensitivity, precision and accuracy, which we provide to our customers.</blockquote><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Bioanalytic_Determination_of_nitrosamine_content_Bioanalytic_1_d629e00e62.jpg" alt="Bioanalytic: Determination of nitrosamine content." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Bioanalytic_Determination_of_nitrosamine_content_Bioanalytic_1_d629e00e62.jpg 103w," sizes="100vw" width="1130" height="1710">

Identification of the proteins (Bioanalytic)

We perform proteomic analyses on a state-of-the-art high-resolution ZenoTOF 7600 (SCIEX), in which the Zeno ion trap and EAD (Electron-Activated Dissociation) technology together make a powerful combination.

Protein identification is based on experimental measurement of peptide molecular weights and matching the amino acid sequence of the protein under study with protein sequences deposited in libraries (databases). Two approaches are most commonly used in proteomic studies: top-down and bottom-up. The top-down method involves analyzing full protein sequences. Bottom-up analyses, on the other hand, use digestion of proteins with proteolytic enzymes. The peptides obtained by digestion are analyzed using a mass spectrometer. Each analysis leads to a comparison of experimental data with data obtained by theoretical digestion of proteins described in the database.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Bioanalytic_Identification_of_the_proteins_Bioanalytic_2_6231b73f0d.jpg" alt="Bioanalytic: Identification of the proteins." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Bioanalytic_Identification_of_the_proteins_Bioanalytic_2_6231b73f0d.jpg 245w," sizes="100vw" width="1536" height="766"><h4>LC-MS/MS</h4>Tandem mass spectrometers are commonly used to determine protein sequences. They allow ion selection of pseudomolecular peptides and then fragmentation and measurement of the masses of the resulting fragments. Fragmentation using collision induced dissociation(CID ) is an invaluable tool in targeted and untargeted MS/MS analysis of small molecules. It is important to note that in proteomic analysis, data obtained using the aforementioned fragmentation method may leave gaps. For example, spectra obtained by CID fragmentation do not allow unambiguous differentiation of some amino acids: leucine from isoleucine (identical molar masses and CID fragmentation) and lysine from glutamine (very similar masses). For this reason, we perform proteomic analyses on a state-of-the-art high-resolution <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/library?manufacturerItems=52&amp;search=+ZenoTOF+7600">ZenoTOF 7600</a> (SCIEX), in which the Zeno ion trap and EAD (Electron-Activated Dissociation) technology together make a powerful combination. It enables the creation of unique fragments to differentiate problematic amino acids and increase the sensitivity and specificity of the analysis.<blockquote>We perform analyses of:<ul><li>samples from solution;</li><li>samples from a gel;</li><li>samples from a complex matrix (by prior arrangement);</li><li>samples from lyophilizer;</li><li>samples previously prepared by the client.</li></ul>Qualitative analysis of proteins includes:<ul><li>To confirm the presence of a protein, the sample is subjected to digestion and the result obtained from experimental data is compared with theoretical data;</li><li>Comparison of experimental data on the masses of peptides included in the analyzed protein with the protein sequences described in the database;</li><li>Analysis and identification of the protein mixture;</li><li>Identification of post translational modifications (PTMs) (we use the tools: Skyline, Spectronaut).</li><li>Reporting of the result including, but not limited to, confirmation of the coverage of the protein sequence obtained in the test sample with the theoretical protein and the list of modified peptides, location and % of modifications.</li></ul>Comparative analyses include:<ul><li>Determining the composition of mixtures;</li><li>Comparison and profiling of sample series - protein identification and trend analysis.</li></ul>Our offer also includes:<ul><li>Support in the planning and execution of studies (the scope is determined individually);</li><li>Assistance in the development of extraction methods from complex matrices - biological fluids, plant tissue, animal tissues (the scope is determined individually);</li><li>Statistical analysis using tools: MarkerView (PCA), GraphPad Prism, Trends, Sciex OS;</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/1294">Quantitative analysis of proteins</a>;</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/1296">Analysis and characterization of monoclonal antibodies</a>.</li></ul></blockquote><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Bioanalytic_Identification_of_the_proteins_Bioanalytic_1_97cf8c94b3.jpg" alt="Bioanalytic: Identification of the proteins." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Bioanalytic_Identification_of_the_proteins_Bioanalytic_1_97cf8c94b3.jpg 117w," sizes="100vw" width="1500" height="2000">

Common GLP-1 Peptide Blind Test (Semaglutide, Tirzepatide and Retatrutide)

Blind HPLC analysis of semaglutide, tirzepatide and retatrutide. Identify the peptide, determine its amount and purity, and choose from a range of additional laboratory analyses.

The Common GLP-1 Peptide Blind Test is a comprehensive laboratory analysis designed to identify the three most common GLP-1 peptides—semaglutide, tirzepatide, and retatrutide. Using HPLC, the test identifies the peptide present in the sample, accurately measures its amount, and determines peptide purity. If multiple target peptides are present, all detected compounds are identified and quantified.Because this is a blind analysis, there is no need to specify which peptide is expected in the sample before submission.<h3>About the Target Peptides</h3>Semaglutide is a long-acting GLP-1 receptor agonist widely used for the treatment of type 2 diabetes and obesity. Its prolonged activity improves glycemic control while promoting weight loss.Tirzepatide is a dual GIP and GLP-1 receptor agonist that combines two incretin pathways, providing enhanced metabolic effects compared to conventional GLP-1 therapies.Retatrutide is a next-generation triple agonist targeting GLP-1, GIP, and glucagon receptors. It is currently under clinical investigation as a promising therapy for obesity and metabolic disorders.<h4>Key Features</h4><ul><li>Blind identification of semaglutide, tirzepatide, or retatrutide</li><li>Identification of mixtures containing multiple GLP-1 peptides</li><li>Quantification of peptide content</li><li>Peptide purity determination</li><li>HPLC analytical method</li><li>Results reported in mg per vial for lyophilized samples</li><li>Optional m/m purity reporting</li><li>Suitable for lyophilized peptides and raw API powders</li><li>Average turnaround time of 7 business days</li></ul><h4>Analysis Parameters</h4><ul><li>Target compounds: Semaglutide, Tirzepatide, Retatrutide</li><li>Testing method: HPLC</li><li>Detection limit: Less than one twentieth of a standard vial dosage</li><li>Result format (lyophilizate): mg per vial and peptide purity</li><li>Alternative format: m/m purity and peptide purity</li><li>Minimum sample (lyophilizate): One unopened vial</li><li>Minimum sample (raw API): 30 mg in sealed glass vial</li></ul><blockquote>Important Notice: If multiple GLP-1 peptides are present in the same sample, individual peptide purity may not be measurable.</blockquote><h4>Optional Additional Analyses</h4>The following optional laboratory services are available:<ul><li>GLP-1 aggregate analysis</li><li>Trifluoroacetic acid (TFA) analysis</li><li>Complete raw analytical data</li><li>Fentanyl screening</li><li>Batch variance testing</li><li>pH measurement</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2522">Endotoxin (LPS) analysis</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/2526">CHNS mass report</a></li><li>Additional laboratory report</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2524">LC/MS peptide contamination screening</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2527">Sterility testing (TAMC/TYMC)</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/2525">Heavy metals analysis (As, Cd, Pb, Hg)</a></li></ul>

Blind common anabolic steroid and aromatase inhibitors screening – orals (pills, tablets, capsules)

Blind HPLC screening of common anabolic steroids and aromatase inhibitors in pills, tablets, and capsules. The analysis identifies and quantifies all detected target compounds, including mixtures.

The Blind Common Anabolic Steroid and Aromatase Inhibitor Screening is a comprehensive laboratory analysis designed to detect and quantify commonly encountered anabolic-androgenic steroids and aromatase inhibitors in oral products - pills, tablets, and capsules.Because this is a blind analysis, there is no need to specify which substance is expected in the sample before submission. Every target compound included in the screening is assessed, and all detected substances are identified and quantified, including samples containing mixtures of multiple compounds.<h4>About the Target Compounds</h4>Anabolic-androgenic steroids are synthetic derivatives of testosterone or related steroid hormones. They interact with androgen receptors and have both anabolic effects, associated with tissue and muscle growth, and androgenic effects. The screened compounds include substances such as oxandrolone, stanozolol, oxymetholone, methandrostenolone, fluoxymesterone, methasterone, mesterolone, methenolone acetate, and 4-chlorodehydromethyltestosterone. Individual compounds differ considerably in their chemical structure, potency, metabolism, and relative anabolic and androgenic activity.Letrozole, anastrozole, and exemestane are aromatase inhibitors. They inhibit aromatase, the enzyme involved in estrogen biosynthesis, thereby reducing estrogen production. Letrozole and anastrozole are non-steroidal aromatase inhibitors, whereas exemestane is a steroidal aromatase inhibitor. These substances are used medically in hormone-sensitive breast cancer treatment but may also be found in products associated with anabolic steroid use.<h4>Key Features</h4><ul><li>Blind screening with no need to declare the expected compound</li><li>Detection of common anabolic steroids and aromatase inhibitors in oral dosage forms</li><li>Identification of mixtures containing multiple target compounds</li><li>Quantification of every detected target compound</li><li>Suitable for pills, tablets, and capsules</li><li>Results reported in mg per pill, tablet, or capsule</li><li>HPLC analytical method</li><li>Average turnaround time of 7 business days</li></ul><h4>Analysis Parameters</h4><ul><li>Target compounds: Letrozole, anastrozole, exemestane, fluoxymesterone, methandrostenolone, oxandrolone, stanozolol, 4-chlorodehydromethyltestosterone, mesterolone, methenolone acetate, methasterone, and oxymetholone</li><li>Other common names and brand names: Femara, Arimidex, Aromasin, Halotestin, Halo, Anavar, Var, Winstrol, Winny, Turinabol, Tbol, Proviron, Superdrol, Anadrol, Anapolon, Methandienone, Dianabol, and Dbol</li><li>Testing method: HPLC</li><li>Detection limit cutoff:&nbsp;<ul><li>2 mg per pill / tablet / capsule</li><li>Letrozole and anastrozole: 0.2 mg pill / capsule</li></ul></li><li>Result format: mg per pill / tablet / capsule</li><li>Minimum sample amount: One pill / tablet / capsule</li><li>Optimal sample amount: Three pills / tablets / capsules</li><li>Average turnaround time: 7 business days</li></ul><h4>Optional Additional Analyses</h4>The following optional laboratory services are available:<ul><li>Complete Raw Analytical Data</li><li>Batch Variance Testing</li><li>Fentanyl Screening</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2524">GC–MS Contamination Screening</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/2525">Heavy Metals Analysis (As, Cd, Pb, Hg)</a></li><li>Additional Laboratory Report</li></ul>

Blind common anabolic steroid and aromatase inhibitors screening – raws

Blind HPLC screening of common anabolic steroids and aromatase inhibitors in raw API powders. The analysis identifies the target compound and determines its percentage content.

The Blind Common Anabolic Steroid and Aromatase Inhibitor Screening is a comprehensive laboratory analysis designed to identify and quantify commonly encountered anabolic-androgenic steroids and aromatase inhibitors in raw active pharmaceutical ingredient (API) powders.Because this is a blind analysis, there is no need to specify which substance is expected in the sample. The analysis screens for all target compounds listed below and identifies and quantifies any detected substance.<h4>About the Target Compounds</h4>Anabolic-androgenic steroids are synthetic derivatives of testosterone or structurally related steroid hormones. They interact with androgen receptors and produce both anabolic effects, associated with tissue and muscle growth, and androgenic effects. The screening covers testosterone and nandrolone esters, trenbolone derivatives, drostanolone esters, boldenone undecylenate, trestolone acetate, dihydroboldenone cypionate, and several other commonly encountered anabolic steroids.Esterification modifies properties such as solubility and the rate at which a steroid is released after administration. For this reason, the panel includes multiple ester forms of testosterone, trenbolone, nandrolone, drostanolone, methenolone, and other steroid compounds.Letrozole, anastrozole, and exemestane are aromatase inhibitors. They inhibit aromatase, the enzyme involved in estrogen biosynthesis, thereby reducing estrogen production. Letrozole and anastrozole are non-steroidal aromatase inhibitors, whereas exemestane is a steroidal inhibitor.<h4>Key Features</h4><ul><li>Blind screening with no need to declare the expected compound</li><li>Identification of common anabolic steroids and aromatase inhibitors in raw API powders</li><li>Broad panel covering steroid bases, esters, and aromatase inhibitors</li><li>Quantification of the detected target compound</li><li>Analysis by HPLC</li><li>Results reported as percentage content</li><li>Average turnaround time of 7 business days</li><li>Minimum sample amount of 200 mg of raw powder</li></ul><h4>Analysis Parameters</h4><ul><li>Target compounds: testosterone propionate, testosterone phenylpropionate, testosterone isocaproate, testosterone enanthate, testosterone cypionate, testosterone decanoate, trenbolone base, trenbolone acetate, trenbolone enanthate, trenbolone hexahydrobenzylcarbonate, trestolone acetate, nandrolone phenylpropionate, nandrolone decanoate, drostanolone propionate, drostanolone enanthate, dihydroboldenone cypionate, boldenone undecylenate, letrozole, anastrozole, dihydrotestosterone (DHT), exemestane, fluoxymesterone, methandrostenolone, oxandrolone, stanozolol, 4-chlorodehydromethyltestosterone, mesterolone, methasterone, oxymetholone, methenolone acetate, methenolone enanthate, and testosterone base</li><li>Other common names and brand names: Andriolos, Parabolan, MENT, NPP, Deca, BU, Equipoise, EQ, Parenabol, Femara, Arimidex, Aromasin, Halotestin, Halo, Anavar, Var, Winstrol, Turinabol, Proviron, Anadrol, Anapolon, Primobolan, Test E, Test C, Methandienone, Dianabol, and Dbol</li><li>Testing method: HPLC</li><li>Detection limit cutoff: 50%</li><li>Result format: % [98%+, 96%+ or % value such as 94.15%]</li><li>Minimum sample amount: 200 mg of raw powder</li><li>Average turnaround time: 7 business days</li></ul><blockquote>Important Notice: The detection cutoff is 50%. Samples containing a target compound below this level may therefore fall outside the standard scope of the screening.</blockquote><h4>Optional Additional Analyses</h4>The following optional laboratory services are available:<ul><li>Complete Raw Analytical Data</li><li>Fentanyl Screening</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2524">GC–MS Contamination Screening</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/2525">Heavy Metals Analysis (As, Cd, Pb, Hg)</a></li><li>Additional Laboratory Report</li></ul>

Blind common anabolic steroid screening – ID only

Blind HPLC identification of common anabolic steroids and selected aromatase inhibitors in oils, oral products, and raw API powders. The analysis reports the detected compound without quantification.

The Blind Common Anabolic Steroid Screening – ID Only is a laboratory analysis designed to identify commonly encountered anabolic-androgenic steroids and selected aromatase inhibitors in an unknown sample. The test is suitable for oil-based samples, oral dosage forms such as tablets and capsules, and raw active pharmaceutical ingredient (API) powders.Because this is a blind analysis, there is no need to specify which substance is expected in the sample. The analysis screens for all target compounds listed below and reports the identity of the detected compound.<h4>About the Target Compounds</h4>Anabolic-androgenic steroids are synthetic derivatives of testosterone or structurally related steroid hormones. They interact with androgen receptors and produce both anabolic effects, associated with tissue and muscle growth, and androgenic effects.The analysis covers testosterone, trenbolone, nandrolone, drostanolone, methenolone, boldenone, and other commonly encountered anabolic steroids. It includes both non-esterified steroid bases and esterified forms, which differ in properties such as solubility and release rate after administration.The screening also includes letrozole, anastrozole, and exemestane. These compounds are aromatase inhibitors that reduce estrogen production by inhibiting the aromatase enzyme. Letrozole and anastrozole are non-steroidal inhibitors, whereas exemestane is a steroidal aromatase inhibitor.<h4>Key Features</h4><ul><li>Blind identification with no need to declare the expected compound</li><li>Identification of common anabolic steroids and selected aromatase inhibitors</li><li>Suitable for oil-based samples, tablets, capsules, and raw API powders</li><li>Broad selection of steroid bases and esterified compounds</li><li>Analysis by HPLC</li><li>Results reported as the name of the detected compound</li><li>Average turnaround time of 7 business days</li><li>Minimum sample requirements adapted to the submitted sample type</li></ul><h4>Analysis Parameters</h4><ul><li>Target compounds: testosterone propionate, testosterone phenylpropionate, testosterone isocaproate, testosterone enanthate, testosterone cypionate, testosterone decanoate, trenbolone base, trenbolone acetate, trenbolone hexahydrobenzylcarbonate, trestolone acetate, nandrolone phenylpropionate, nandrolone decanoate, drostanolone propionate, drostanolone enanthate, dihydroboldenone cypionate, boldenone undecylenate, letrozole, anastrozole, exemestane, fluoxymesterone, methandrostenolone, oxandrolone, stanozolol, 4-chlorodehydromethyltestosterone, mesterolone, methasterone, oxymetholone, methenolone acetate, methenolone enanthate, and testosterone base</li><li>Testing method: HPLC</li><li>Result format: Name of the AAS found in the sample</li><li>Minimum sample amount&nbsp;<ul><li>oils: 0.5–1 mL</li><li>oral products: One tablet or capsule</li><li>raw powders: 200 mg</li></ul></li><li>Average turnaround time: 7 business days</li></ul><blockquote>Important Notice: This analysis provides compound identification only. The amount, concentration, or percentage content of the detected substance is not measured.</blockquote><h4>Optional Additional Analyses</h4>The following optional laboratory services are available:<ul><li>Fentanyl Screening</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2524">GC–MS Contamination Screening</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/2525">Heavy Metals Analysis (As, Cd, Pb, Hg)</a></li><li>Additional Laboratory Report</li></ul>

Blind common anabolic steroid screening – oils

Blind HPLC screening of common anabolic steroids in oil-based samples. The analysis identifies and quantifies all detected target compounds, including mixtures.

The Blind Common Anabolic Steroid Screening – Oils is a comprehensive laboratory analysis designed to identify and quantify commonly encountered anabolic-androgenic steroids in oil-based samples.Because this is a blind analysis, there is no need to specify which substance is expected in the sample. The analysis screens for all target compounds listed below and identifies and quantifies every detected substance, including samples containing mixtures of multiple compounds.<h4>About the Target Compounds</h4>Anabolic-androgenic steroids are synthetic derivatives of testosterone or structurally related steroid hormones. They interact with androgen receptors and produce both anabolic effects, associated with tissue and muscle growth, and androgenic effects.The analysis covers several esterified forms of testosterone, trenbolone, nandrolone, drostanolone, methenolone, and boldenone, as well as testosterone undecanoate, methyltestosterone, trestolone acetate, and dihydrotestosterone (DHT).Esterification influences properties such as solubility and the rate at which a steroid is released after administration. Different ester forms of the same steroid may therefore differ in their physicochemical and pharmacokinetic characteristics.<h4>Key Features</h4><ul><li>Blind screening with no need to declare the expected compound</li><li>Identification and quantification of common anabolic steroids in oil-based samples</li><li>Detection of mixtures containing multiple target compounds</li><li>Broad range of steroid bases and esterified compounds</li><li>Analysis by HPLC</li><li>Results reported in mg/mL</li><li>Average turnaround time of 7 business days</li><li>Minimum sample amount of 0.5–1 mL of oil</li></ul><h4>Analysis Parameters</h4><ul><li>Target compounds: testosterone propionate, testosterone phenylpropionate, testosterone isocaproate, testosterone enanthate, testosterone cypionate, testosterone decanoate, testosterone undecanoate, methyltestosterone, trenbolone acetate, trenbolone enanthate, trenbolone hexahydrobenzylcarbonate, trestolone acetate, dihydrotestosterone (DHT), nandrolone phenylpropionate, nandrolone cypionate, nandrolone decanoate, drostanolone propionate, drostanolone enanthate, dihydroboldenone cypionate, methenolone enanthate, boldenone acetate, boldenone cypionate, and boldenone undecylenate</li><li>Other common names and brand names: Sustanon, Test E, Test C, Deca, Tren, Parabolan, MENT, NPP, Masteron, Masteron Propionate, Mast P, Masteron Enanthate, Mast E, Primobolan, Primo E, BU, Equipoise, EQ, and Parenabol</li><li>Testing method: HPLC</li><li>Detection limit cutoff:&nbsp;<ul><li>15 mg/mL</li><li>drostanolone propionate and drostanolone enanthate: 25 mg/mL</li></ul></li><li>Result format: mg/mL</li><li>Minimum sample amount: 0.5–1 mL of oil</li><li>Average turnaround time: 7 business days</li></ul><blockquote>Important Notice: The standard detection cutoff is 15 mg/mL. For drostanolone propionate and drostanolone enanthate, the cutoff is 25 mg/mL. Target compounds present below these levels may not be reliably detected or quantified within the standard scope of the analysis.</blockquote><h4>Optional Additional Analyses</h4>The following optional laboratory services are available:<ul><li>Benzyl Alcohol and Benzyl Benzoate Testing</li><li>Complete Raw Analytical Data</li><li>Fentanyl Screening</li><li>pH Measurement</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2524">GC–MS Contamination Screening</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2527">Sterility Testing (TAMC and TYMC)</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/2525">Heavy Metals Analysis (As, Cd, Pb, Hg)</a></li><li>Additional Laboratory Report</li></ul>

DHT enanthate analysis

Targeted HPLC analysis of DHT enanthate in oil-based samples and raw API powders. The test confirms compound identity and determines its content in mg/mL or percentage.

The DHT Enanthate Analysis is a targeted laboratory test designed to confirm the identity and determine the amount of dihydrotestosterone enanthate in oil-based samples and raw active pharmaceutical ingredient (API) powders.The analysis specifically targets DHT enanthate. Samples expected to contain non-esterified DHT should instead be submitted for the appropriate blind common anabolic steroid screening for <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2478">oils </a>or<a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2476"> raw API powders</a>.<h4>About DHT Enanthate</h4>DHT enanthate, also known as dihydrotestosterone heptanoate, is an esterified form of DHT designed for slower release and potentially prolonged activity. The enanthate group increases the compound’s lipophilicity. After release, DHT activates androgen receptors and, unlike testosterone, cannot be converted into estradiol by aromatase.<h4>Key Features</h4><ul><li>Targeted identification and quantification of DHT enanthate</li><li>Suitable for oil-based samples and raw API powders</li><li>Analysis by HPLC</li><li>Results for oil samples reported in mg/mL</li><li>Results for raw API powders reported as percentage content</li><li>Optional mass-by-mass purity reporting for raw API powders</li><li>Minimum sample amount of 0.5–1 mL for oil samples</li><li>Minimum sample amount of 200 mg for raw API powders</li><li>Average turnaround time of 7 business days</li></ul><h4>Analysis Parameters</h4><ul><li>Target compound: DHT enanthate</li><li>Testing method: HPLC</li><li>Detection limit cutoff: 15 mg/mL</li><li>Result format for oil samples: mg/mL</li><li>Minimum sample amount for oil samples: 0.5–1 mL</li><li>Result format for raw API powders: % [98%+, 96%+ or % value such as 94.15%]</li><li>Minimum sample amount for raw API powders: 200 mg</li><li>Average turnaround time: 7 business days</li></ul><blockquote>Important Notice: This analysis is intended specifically for DHT enanthate. It is not designed for the analysis of non-esterified DHT.</blockquote><h4>Optional Additional Analyses</h4>The following optional laboratory services are available:<ul><li>Benzyl Alcohol and Benzyl Benzoate Testing</li><li>Complete Raw Analytical Data</li><li>Alternative Result Format: Mass-by-Mass Purity - only for raw API powders</li><li>pH Measurement</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2524">GC–MS Contamination Screening</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2527">Sterility Testing (TAMC and TYMC)</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/2525">Heavy Metals Analysis (As, Cd, Pb, Hg)</a></li><li>Additional Laboratory Report</li></ul>

Epistane analysis

Targeted HPLC analysis of epistane in tablets, capsules, and raw API powders. The test confirms compound identity and determines its content in mg per unit or as a percentage.

The Epistane Analysis is a targeted laboratory test designed to confirm the identity and determine the amount of epistane in oral dosage forms and raw active pharmaceutical ingredient (API) powders.&nbsp;The analysis is suitable for tablets and capsules, with results reported in milligrams per individual dosage unit. Raw API powders can be evaluated by percentage content, with optional purity reporting in % (m/m).<h4>About Epistane</h4>Epistane, also known as methylepitiostanol or 2,3-thioepoxy madol, is a synthetic, orally active anabolic-androgenic steroid structurally related to dihydrotestosterone (DHT). It is a 17α-methylated derivative of epitiostanol and interacts with androgen receptors, producing anabolic and androgenic effects.Epistane has been identified in products marketed as dietary or performance-enhancing supplements. Scientific studies have also associated its use with a risk of liver injury, including cholestasis.<h4>Key Features</h4><ul><li>Targeted identification and quantification of epistane</li><li>Suitable for tablets, capsules, and raw API powders</li><li>Analysis by HPLC</li><li>Results for oral products reported in mg per tablet or capsule</li><li>Results for raw API powders reported as percentage content</li><li>Optional purity reporting in % (m/m) for raw API powders</li><li>Minimum sample amount of three tablets or capsules</li><li>Minimum sample amount of 200 mg for raw API powders</li><li>Average turnaround time of 7 business days</li></ul><h4>Analysis Parameters</h4><ul><li>Target compound: Epistane</li><li>Other names: Hemapolin, 2,3-thioepoxy madol</li><li>CAS number: 4267-80-5</li><li>Testing method: HPLC</li><li>Minimum amount of target compound for evaluation in oral products: 4 mg per tablet / capsule</li><li>Minimum content of target compound for evaluation in raw API powders: 10%</li><li>Result format for oral products: mg per tablet or capsule</li><li>Result format for raw API powders: % [98%+, 96%+ or % value such as 94.15%]</li><li>Minimum sample amount for oral products: 3 tablets / capsules</li><li>Minimum sample amount for raw API powders: 200 mg</li><li>Average turnaround time: 7 business days</li></ul><h4>Optional Additional Analyses</h4>The following optional laboratory services are available:<ul><li>Complete Raw Analytical Data</li><li>Alternative Result Format: Purity in % (m/m) - only for raw API powders</li><li>Batch Variance Testing</li><li>Fentanyl Screening</li><li><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2524">GC–MS Contamination Screening</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/2525">Heavy Metals Analysis (As, Cd, Pb, Hg)</a></li><li>Additional Laboratory Report</li></ul>

Human Growth Hormone amount, purity and dimer and higher molecular weight proteins analysis

Laboratory analysis of HGH 191 AA determines identity, amount, purity, dimer content and higher molecular weight proteins in lyophilizates, liquids and raw API powders.

This analysis is designed to identify Human Growth Hormone 191 AA and determine its amount and purity. The test also includes separate measurement of HGH dimer and higher molecular weight proteins, which are important quality parameters for growth hormone products.<h4>Human Growth Hormone 191 AA</h4>Human Growth Hormone, also known as HGH, somatropin or recombinant human growth hormone (rHGH), is a peptide hormone composed of 191 amino acids. It is naturally involved in the regulation of growth, metabolism and other physiological processes.Somatropin used in pharmaceutical products is a recombinant form corresponding to the naturally occurring 191-amino-acid human growth hormone. Product quality depends not only on HGH content and purity but also on the presence of dimers and other higher molecular weight protein forms.An HGH dimer is formed when two growth hormone molecules associate with each other. Because the dimer is still composed of HGH molecules, it may not be classified as a conventional impurity by a standard purity test. A separate analysis is therefore required for its accurate measurement. Increased levels of dimers and other high-molecular-weight protein forms may affect product quality, activity and tolerability.<h4>What the Analysis Determines</h4><ul><li>Identity of HGH 191 AA</li><li>Amount of HGH in the sample</li><li>Growth hormone purity</li><li>Dimer content</li><li>Higher molecular weight protein content</li><li>Results in a format appropriate for the submitted sample type</li></ul><h4>Analysis Parameters</h4><ul><li>Target compound: Human Growth Hormone 191 AA</li><li>Other names: somatropin, HGH, rHGH, 191 AA</li><li>Molecular weight: 22,124 Da</li><li>Testing method: HPLC</li><li>HGH detection limit: 0.2 mg/ml or 0.5 mg/vial</li><li>Dimer and higher molecular weight protein detection limit: 0.008%</li><li>Result format for lyophilizates: mg/vial, IU, purity percentage and dimer percentage</li><li>Result format for liquids: mg/ml, IU, purity percentage and dimer percentage</li><li>Alternative result format: m/m purity, GH purity and dimer percentage</li><li>Minimum lyophilizate sample: one whole unopened vial containing the lyophilizate</li><li>Minimum liquid sample: 1 ml</li><li>Minimum raw API powder sample: 30 mg in a sealed glass vial to prevent moisture absorption</li><li>Average turnaround time: 7 business days</li></ul><h4>Important Notice</h4>Only the 191-amino-acid form of HGH is recognized as Human Growth Hormone by this analytical method. HGH 192 AA is not a target of the test and its presence would result in “HGH not detected” being stated in the report.The alternative m/m purity result format is intended exclusively for raw API powders. Lyophilized products are normally reported in mg/vial, while liquid samples are reported in mg/ml.<h4>Additional Analyses</h4><h5>TFA Analysis</h5><ul><li>Detection and measurement of trifluoroacetic acid (TFA) in the sample. Results are reported in mg per vial.</li></ul><h5>Raw Data</h5><ul><li>Delivery of the available raw analytical data from the primary test and all applicable additional analyses.</li></ul><h5>Fentanyl Presence Analysis</h5><ul><li>Screening of the sample for the presence of fentanyl.</li></ul><h5>Alternative Result Format – m/m Purity</h5><ul><li>Alternative reporting of the result as mass-by-mass purity. This option is intended exclusively for raw API powders.</li></ul><h5>Variance Testing with Dimer Analysis</h5><ul><li>Analysis of multiple vials from the same batch to evaluate variation in HGH content, purity and dimer levels. Dimer content is measured in every submitted vial.</li></ul><h5>Variance Testing</h5><ul><li>Analysis of multiple sample units from the same product batch to assess variation between individual vials or units. Dimer is not measured in the additional samples under this option.</li></ul><h5>pH Measurement</h5><ul><li>Measurement of the sample’s pH value.</li></ul><h5><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2522">Endotoxin Analysis</a></h5><ul><li>Measurement of bacterial endotoxins, particularly lipopolysaccharides (LPS), in the sample. This analysis is available only for finished products and should not be ordered for raw powders.</li><li>The standard test provides accurate results up to 10 EU/vial. Values above 10 EU/vial are estimated and require an additional test with a different dilution for precise determination. Sending two vials is therefore recommended. Where endotoxin levels above 10 EU/vial are expected, the method can be calibrated for the higher range in advance.</li></ul><h5><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/2526">CHNS Mass Report</a></h5><ul><li>Elemental analysis providing accurate measurement of nitrogen and sulphur content. The results can be used to determine Net Peptide Content (NPC).</li></ul><h5>Additional Report</h5><ul><li>A separate additional laboratory report issued under a different client name.</li></ul><h5><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2524">LC-MS Screening for Peptide Contamination</a></h5><ul><li>LC-MS screening for contamination with other peptides or peptide degradation products. Detection is limited to peptides included in the laboratory’s available testing database.</li><li>The initial screening provides identification only. If contamination is detected, quantitative measurement may subsequently be ordered.</li></ul><h5><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2527">Sterility Testing</a></h5><ul><li>TAMC and TYMC testing checks the product for the presence of bacteria, yeasts and moulds. Additional unopened sample units must be submitted for the analysis. The average turnaround time for sterility testing is 14 days.</li></ul><h5><a target="_blank" rel="noopener noreferrer" href="https://icpms.labrulez.com/products/2525">Heavy Metals Analysis</a></h5><ul><li>Detection of selected heavy metals in the sample.</li></ul>

Products from category Pharmaceutical analyses - page 9

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