Scientists at IOCB Prague are uncovering new details of gene transcription. They have identified a previously unknown molecular mechanism by which the transcription of genetic information from deoxyribonucleic acid (DNA) into ribonucleic acid (RNA) can be initiated. The researchers focused on a specific class of molecules known as alarmones, which are found in cells across a wide range of organisms and whose levels often increase under conditions of cellular stress. The results were published in the prestigious scientific journal Nature Chemical Biology.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_bc2bfffa6c.jpg" alt="IOCB Prague/Tomáš Belloň: Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription: Dr. Hana Cahová, head of the Chemical Biology of Nucleic Acids research group." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_bc2bfffa6c.jpg 234w," sizes="100vw" width="2000" height="1335"><div>Molecules of ribonucleic acid can carry a variety of chemical modifications at one end, known as caps. In eukaryotic organisms, including human cells, the best-known cap plays an important role in RNA stability and in regulating its subsequent fate. In recent years, however, it has become clear that alternative, non-canonical RNA caps also exist, although their formation and the mechanisms by which they are attached to RNA remain only partially understood. These include alarmone caps, formed by dinucleoside polyphosphate molecules, that protect cellular RNA at moments when the cell is under threat.In their study, <a target="_blank" rel="noopener noreferrer" href="https://cahova.group.uochb.cz/en">Dr. Hana Cahová</a> and colleagues examined bacterial RNA polymerase and investigated how this enzyme can initiate transcription using dinucleoside polyphosphates (NpNs) instead of the standard RNA building blocks. For the first time, the scientists described, at the atomic level, how RNA bearing an alarmone cap can be generated directly at the initiation of gene transcription. They also observed that NpNs bind through a different type of base pairing than is typically observed.The work was significantly shaped by Valentina Serianni from Hana Cahová’s team, who demonstrated the ability of dinucleoside polyphosphates to initiate gene transcription, and by Jana Škerlová, who focused on the structural analysis of RNA polymerase. Using cryogenic electron microscopy data, she showed how dinucleoside polyphosphate molecules bind within the active site of RNA polymerase – that is, the core of the enzyme where genetic information is transcribed. Together, their findings help to elucidate the processes that accompany the transcription of genetic information from DNA to RNA.Hana Cahová adds: “We’re describing something that truly occurs in cells and that we’re now able to observe directly at the level of individual molecules. This allows us to answer fundamental questions about cellular processes, such as how cells adapt to stress. RNA plays a central role in this, as it carries the cascade of information underlying any cellular response – for example, to threatening conditions caused by nutrient deprivation or temperature shock.”<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_2_0fe88ff9e9.jpg" alt="IOCB Prague/Tomáš Belloň: Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription: Dr. Tomáš Kouba, head of the Cryogenic Electron Microscopy core facility." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_2_0fe88ff9e9.jpg 234w," sizes="100vw" width="2000" height="1335"><div>Cryogenic electron microscopy (cryo-EM) was central to the project. This part of the work was led by Dr. Tomáš Kouba, one of the authors of the study. “Cryogenic electron microscopy allows us to freeze biological molecules in a state very close to their natural form and then determine their three-dimensional structure. This makes it possible to look directly into the active centers of enzymes and observe their function down to the atomic level,” he explains.Last year, IOCB Prague opened a new <a target="_blank" rel="noopener noreferrer" href="https://cryoem.group.uochb.cz/en">cryo-EM center</a> that is unique within the Czech research environment. State-of-the-art cryogenic electron microscopes are housed in a specially designed building and enable the study of biological processes with exceptional structural precision.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_3_4d881e7a58.jpg" alt="IOCB Prague: Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription: This work shows how NpnNs initiate bacterial transcription. Cryo-EM reveals how nucleobases pair with the template: one in canonical and one in reverse Watson–Crick mode, providing a structural basis for their function as non-canonical RNA caps." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_3_4d881e7a58.jpg 245w," sizes="100vw" width="2000" height="1077"><blockquote><h4>The Original article</h4><h4><a target="_blank" rel="noopener noreferrer" href="https://www.nature.com/articles/s41589-025-02134-5">Molecular insight into 5′ RNA capping with NpnNs by bacterial RNA polymerase</a></h4>Valentina M. Serianni, Jana Škerlová, Anna Knopp Dubánková, Anton Škríba, Hana Šváchová, Tereza Vučková, Anatolij Filimoněnko, Milan Fábry, Pavlína Řezáčová, Tomáš Kouba &amp; Hana Cahova&nbsp;Nat. Chem. Biol. 21 (2026)<a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1038/s41589-025-02134-5">https://doi.org/10.1038/s41589-025-02134-5</a><h6>licensed under <a target="_blank" rel="noopener noreferrer" href="https://creativecommons.org/licenses/by/4.0/">CC-BY 4.0</a></h6></blockquote><h4>Abstract</h4>RNA capped with dinucleoside polyphosphates has been discovered in bacteria and eukaryotes only recently. The likely mechanism of this specific capping involves direct incorporation of dinucleoside polyphosphates by RNA polymerase as noncanonical initiating nucleotides. However, how these compounds bind into the active site of RNA polymerase during transcription initiation is unknown. Here, we explored transcription initiation in vitro, using a series of DNA templates in combination with dinucleoside polyphosphates and model RNA polymerase from Thermus thermophilus. We observed that the transcription start site can vary on the basis of the compatibility of the specific template and dinucleoside polyphosphate. Cryo-electron microscopy structures of transcription initiation complexes with dinucleoside polyphosphates revealed that both nucleobase moieties can pair with the DNA template. The first encoded nucleotide pairs in a canonical Watson–Crick manner, whereas the second nucleobase pairs noncanonically in a reverse Watson–Crick manner. Our work provides a structural explanation of how dinucleoside polyphosphates initiate RNA transcription.</div></div>

Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription

Food adulteration is a phenomenon with a long history that has gained increasing importance in recent years due to the globalization of food supply chains and strong economic pressures. Whether it involves diluting olive oil with cheaper oils, adding sugar to honey, or the hidden use of substitutes in protein supplements, the result is a loss of consumer trust and, in some cases, a potential risk to health. Analytical chemistry plays a key role in this area by providing methods and technologies capable of identifying and quantifying target compounds as well as unwanted impurities in a wide range of food matrices.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Watrex_Praha_Falsovani_potravin_a_jak_ho_odhali_analyticka_chemie_6912db5492.jpg" alt="Watrex: Food Adulteration and How It Is Revealed by Analytical Chemistry" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Watrex_Praha_Falsovani_potravin_a_jak_ho_odhali_analyticka_chemie_6912db5492.jpg 245w," sizes="100vw" width="1600" height="900"><h4>The Role of Chromatography in Forensic Food Analysis</h4>Chromatography, particularly liquid chromatography (HPLC), is one of the most effective analytical tools for separating complex mixtures of molecules. It enables:<ul><li>qualitative identification of individual components in a sample,</li><li>quantitative determination of their concentrations,</li><li>detection of impurities and unexpected components that may indicate adulteration.</li></ul>In practice, HPLC is often combined with various types of detectors (UV/VIS, DAD, refractive index detectors) or with other techniques (e.g., mass spectrometry) to increase selectivity and sensitivity.<h4>Isocratic vs. Gradient Elution</h4>In the analysis of food samples, chromatographic methods are selected according to the analytical goal:<ul><li>Isocratic HPLC uses a constant mobile phase composition throughout the analysis. It is simple, robust, and ideal for routine determinations of well-defined target analytes (e.g., sugars or vitamins).</li><li>Gradient HPLC changes the mobile phase composition during separation, enabling better resolution of complex mixtures with a wide range of polarities (e.g., peptides or phenolic compounds).</li></ul>Gradient methods are particularly useful when analytes have very different properties and high separation efficiency is required.<h4>Watrex Praha and the Contribution of Modern Systems to Food Analysis</h4><a target="_blank" rel="noopener noreferrer" href="https://watrex.com/?utm_source=labrulez&amp;utm_medium=propagace&amp;utm_campaign=labrulez_clanky_HPLCsystemy">Watrex Praha, s.r.o.</a> is one of the leading Czech manufacturers and distributors of liquid chromatography systems and instruments, with a long tradition dating back to 1990. The company has successfully transformed from a distributor into a manufacturer of its own HPLC and related technologies, focusing on modular, robust systems suitable even for demanding analytical tasks.Their <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products?manufacturerItems=93&amp;search=streamline">Streamline™ product line</a> includes several HPLC system concepts suitable for food analysis:<ul><li>Isocratic HPLC system – a simple yet precise configuration with a single pump, column thermostat, and UV/VIS detector; suitable for routine determination of known analytes (e.g., basic carbohydrates, food additives).</li><li>Binary gradient HPLC system – equipped with two pumps enabling mobile phase gradient formation, which enhances separation performance for complex mixtures (e.g., phenolic profiles of wine, components of aromatic extracts).</li><li>GPC/SEC system (Gel Permeation / Size Exclusion Chromatography) – a specialized solution for the determination of macromolecules and polymers, also relevant for the analysis of high-molecular-weight components in foods (e.g., polysaccharides).</li></ul><blockquote>👉<a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/labrulez-bucket-strapi-h3hsga3/Watrex_catalog_2024_ba97395f92.pdf">Product catalogue HERE</a></blockquote>Thanks to the modular nature of these systems, analysts can easily adapt the configuration to a specific analytical problem, from simple routine analyses to complex characterization of food samples.<h4>Practical Examples of Adulteration Revealed by HPLC</h4><ul><li>Detection of olive oil dilution: HPLC can separate and quantify characteristic triacylglycerols and fatty acids; unusual patterns indicate the presence of cheaper oils.</li><li>Estimation of sugar addition in honey: Isocratic HPLC with a refractive index detector can determine sugar profiles (glucose, fructose, sucrose), revealing dilution or the addition of sugar syrups.</li><li>Identification of aromatic adulterants in wine: Gradient HPLC with a PDA detector can reveal phenolic and aromatic profiles that are altered by the addition of synthetic compounds.</li></ul><h4>Conclusion</h4>Food adulteration remains a current issue that requires reliable and sensitive analytical methods. Liquid chromatography, and in particular modern HPLC systems, represent one of the most powerful tools for detecting unwanted additives, impurities, and unexpected components in complex food samples. Manufacturers such as <a target="_blank" rel="noopener noreferrer" href="https://watrex.com/?utm_source=labrulez&amp;utm_medium=propagace&amp;utm_campaign=labrulez_clanky_HPLCsystemy">Watrex Praha</a> provide flexible chromatographic platforms covering a wide range of analytical tasks from simple isocratic to advanced gradient and GPC/SEC applications thereby supporting analysts in ensuring food quality and consumer protection.<blockquote>Did you find this article interesting? Follow <a target="_blank" rel="noopener noreferrer" href="https://watrex.com/?utm_source=labrulez&amp;utm_medium=propagace&amp;utm_campaign=labrulez_clanky_HPLCsystemy">Watrex Praha</a> on their social media (<a target="_blank" rel="noopener noreferrer" href="https://www.linkedin.com/company/watrex/?viewAsMember=true">LinkedIn</a> and <a target="_blank" rel="noopener noreferrer" href="https://www.facebook.com/WatrexPrague">Facebook</a>) for more engaging topics.</blockquote>

Food Adulteration and How It Is Revealed by Analytical Chemistry

Join us for a fascinating conversation with Dr. Subhoja Chakraborty from the University of Central Florida, whose cutting-edge research targets the global challenge of malaria drug resistance. Dr. Chakraborty shares her journey from structure-based drug design during her PhD to her recent collaborative work repurposing human kinase inhibitors as rapid, selective antimalarials against drug-resistant Plasmodium falciparum strains.<h4>In this episode, you'll learn:</h4><ul><li>How structure-guided approaches reveal potential drug targets, including cysteine proteases like falcipain-2, and kinases implicated in malaria's complex life cycle.</li><li>The power of repurposing kinase inhibitors originally developed for cancer and other diseases, focusing on compound 12, which blocks hemozoin formation and protein kinase 6—key steps in parasite survival.</li><li>Lab techniques such as affinity, gel filtration, and size exclusion chromatography for recombinant protein purification—and how troubleshooting is crucial for high-yield, stable complexes.</li><li>Advances in mass spectrometry for characterizing protein interactions, validating drug targets, and mapping molecular pathways pivotal to malaria therapeutics.</li><li>Tips and lessons for new researchers facing the challenges of sample preparation, complex protocols, and working as part of a collaborative team.</li></ul>Dr. Chakraborty’s insights bridge the gap between basic science and translational drug discovery, offering hope for more effective, targeted malaria treatments in a world where resistance to frontline therapies threatens millions.<h4>Referenced Papers:</h4><ul><li>"Plasmodium falciparum protein kinase 6 and hemozoin formation are inhibited by a type II human kinase inhibitor exhibiting antimalarial activity" (Cell Chemical Biology, 2025)</li><li>"New insights of falcipain 2 structure from Plasmodium falciparum 3D7 strain" (BBRC, 2022)</li><li>"Structure-Based Optimization of Protease−Inhibitor Interactions to Enhance Specificity of Human Stefin‑A against Falcipain‑2 from the Plasmodium falciparum 3D7 Strain" (Biochemistry, 2023)</li></ul>If you’re a student, scientist, or simply passionate about advances in infectious disease research, this episode offers actionable insights, inspiring advice, and a front-row seat to innovation in combating malaria.<h3>Video Transcription</h3><h4>From Structural Biology to Drug Discovery: Chromatography and Mass Spectrometry in Malaria Research</h4><h5>Introduction</h5>In this discussion, Subhoja shares insights into her research journey, focusing on malaria drug discovery and the role of modern analytical techniques in biological and biomedical research. The conversation is aimed primarily at undergraduate students and early-career researchers interested in chemistry, biotechnology, and life sciences.<h5>Research Focus: Malaria Drug Discovery and Kinase Targets</h5>Subhoja is currently involved in malaria drug discovery research at the University of Central Florida, where she has been working since beginning her postdoctoral position two years ago. Her earlier PhD research focused on structure-based drug design in malaria, using a combination of in silico approaches, recombinant protein expression, and X-ray crystallography to determine precise three-dimensional structures of target proteins and their inhibitors.This structural perspective provided a foundation for her current work, which centers on drug discovery through compound screening and repurposing. A recent publication from her laboratory explores the use of repurposed mammalian CDK-like kinase inhibitors as potential antimalarial agents. While such kinase inhibitors are well known in cancer and cardiovascular research, their application to malaria targets represents a novel and promising approach.Kinases are attractive drug targets because of their central role in cell signaling and growth pathways. By targeting specific kinases involved in different stages of the malaria parasite life cycle—whether asexual growth, gametocytogenesis, or differentiation—it may be possible to significantly inhibit parasite growth and progression.<h5>Chromatography in Protein Expression and Purification Workflows</h5>Chromatography plays a critical role throughout Subhoja’s research. Her experience spans from basic chromatography techniques during her early training to advanced protein purification workflows using affinity chromatography, gel filtration (size exclusion chromatography), and ion exchange chromatography.Recombinant proteins are routinely purified using affinity resins such as nickel or cobalt, followed by further purification to remove contaminants. Fast Protein Liquid Chromatography (FPLC) enables compact, stepwise purification workflows suitable for producing proteins for in vitro assays.A recurring challenge in this process is the expression of high-molecular-weight proteins, which often accumulate in insoluble fractions or inclusion bodies. Careful selection of expression vectors, host systems, and induction conditions is therefore essential to maximize yield and solubility.<h5>Integrating Size Exclusion Chromatography into the Workflow</h5>Size exclusion chromatography (SEC) is typically used after affinity purification to further improve protein purity. Following elution with imidazole or glutathione, desalting is required to prevent buffer components from interfering with downstream assays. This is often achieved using desalting columns such as G-25 or PD-10.To remove lower-molecular-weight contaminants, finer SEC media—such as Superdex or Sephacryl columns—are employed. Concentration steps using molecular-weight cut-off filters are then applied to obtain the desired protein concentration for functional studies.These iterative purification and troubleshooting steps are a routine part of protein biochemistry and reflect the importance of methodical optimization and careful validation.<h5>The Role of Mass Spectrometry in Biomolecular Characterization</h5>Mass spectrometry is a key analytical tool in Subhoja’s research pipeline, particularly for target identification and validation. In both malaria and cancer research, MS is used alongside chromatography, immunoprecipitation, and pull-down assays to study protein interactions and molecular recognition events.Affinity-based mass spectrometry enables the identification of binding partners and interactors, whether studying proteins, long non-coding RNAs, or protein complexes. Techniques such as native MS, tandem affinity purification, and proximity labeling (e.g., TurboID-based workflows) provide deeper insights into molecular networks and signaling pathways.These approaches are essential for understanding how candidate drug targets function within complex biological systems.<h5>Sample Preparation Challenges in Biological Research</h5>Sample preparation remains one of the most challenging aspects of biological experimentation. Whole-cell lysates contain proteases, nucleases, and other components that can rapidly degrade target molecules. Preventing degradation requires minimizing preparation time, maintaining low temperatures, and using appropriate inhibitor cocktails.Reproducibility is also critical: biological experiments require multiple replicates, and variability is often unavoidable. Careful handling, protocol optimization, and continuous troubleshooting are essential to ensure reliable results, whether preparing samples for chromatography, mass spectrometry, sequencing, or immunoprecipitation.<h5>Advances in Chromatography and MS for Malaria Research</h5>Modern advances in chromatography and mass spectrometry significantly enhance malaria research by enabling precise target identification, quantification, and functional characterization. Drug discovery workflows begin with construct design and recombinant expression, followed by purification and interaction studies.In malaria research, stage-specific parasite biology requires careful extraction and analysis of proteins from different life cycle stages. Tandem affinity MS, immunoprecipitation, and in vivo validation studies help confirm target relevance and therapeutic potential.Recent work on repurposed kinase inhibitors has shown promising results, including inhibition of hemozoin formation—a key detoxification pathway for the malaria parasite—highlighting the potential of such compounds for further development.<h5>Malaria, Drug Resistance, and Global Impact</h5>Malaria remains a major global health burden, with over 600,000 deaths annually and widespread drug resistance complicating treatment. Artemisinin resistance, particularly associated with mutations in the K13 propeller domain, has driven the search for new targets and therapies.During her PhD, Subhoja focused on falcipain-2, a cysteine protease involved in hemoglobin degradation within the parasite. This pathway is critical for parasite survival and has emerged as a promising drug target. Her work revealed that falcipain-2 operates within a larger protein complex responsible for hemoglobin processing and amino acid release.Understanding these molecular mechanisms is essential for developing robust, stage-specific antimalarial strategies.<h5>Advice for Early-Career Researchers</h5>For researchers just starting out, Subhoja emphasizes the importance of hands-on experience. Working directly with cells, lysates, and analytical tools is essential for truly understanding experimental systems. Failure is an inherent part of research, and perseverance is key.Motivation, teamwork, careful sample handling, and thorough preparation all contribute to long-term success. Reading extensively, critically evaluating one’s own work, and appreciating incremental progress are vital aspects of a sustainable research career.Every successful experiment—no matter how small—represents meaningful progress and contributes to the broader goals of science and medicine.<h5>Closing Remarks</h5>The discussion highlights how interdisciplinary approaches combining chromatography, mass spectrometry, structural biology, and biochemistry are driving advances in malaria drug discovery. Through careful experimental design, analytical rigor, and collaborative teamwork, researchers can address complex biological challenges and contribute to global health solutions.<blockquote>This text has been automatically transcribed from a video presentation using AI technology. It may contain inaccuracies and is not guaranteed to be 100% correct.</blockquote><blockquote><h4>Concentrating on Chromatography Podcast</h4>Dive into the frontiers of chromatography, mass spectrometry, and sample preparation with host David Oliva. Each episode features candid conversations with leading researchers, industry innovators, and passionate scientists who are shaping the future of analytical chemistry. From decoding PFAS detection challenges to exploring the latest in AI-assisted liquid chromatography, this show uncovers practical workflows, sustainability breakthroughs, and the real-world impact of separation science. Whether you’re a chromatographer, lab professional, or researcher you'll discover inspiring content!You can find Concentrating on Chromatography Podcast in podcast apps:<ul><li><a target="_blank" rel="noopener noreferrer" href="https://open.spotify.com/show/1wZg67rCjoGju4yhqxI3tL">Spotify</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://podcasts.apple.com/tz/podcast/concentrating-on-chromatography/id1788429185">Apple podcast</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://podscan.fm/podcasts/concentrating-on-chromatography">podscan</a></li></ul>and on <a target="_blank" rel="noopener noreferrer" href="https://www.youtube.com/@ChromatographyTalk/videos">YouTube channel</a></blockquote>

Affinity, Gel Filtration, Size Exclusion Chromatography: Repurposing Kinase Inhibitors for Malaria

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The Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences (IOCB Prague) is a leading scientific institution in the Czech Republic, recognized internationally. Its primary mission is basic research in the fields of chemical biology and medicinal chemistry, organic and material oriented chemistry, chemistry of natural compounds, biochemistry and molecular biology, physical chemistry, theoretical chemistry, and analytical chemistry. 

Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences

Organomation, founded in 1959, designs and manufactures high-quality nitrogen evaporators and extraction systems. Known for innovation and durability, their lab instruments are used globally for efficient sample preparation with strong customer support.

Organomation

WATREX Prague is the distributor and producer of HPLC techniques in the Czech Republic and Slovakia. Main Chromatografic and Related Techniques Supported: LC, GPC, IC, IEC, Automated SPE, LC Columns and special column packings, LC method development, Software development, Laboratory Robots.

Watrex Praha

KNAUER AZURA GPC/SEC Systems

AZURA® SEC is KNAUER's line of GPC and SEC systems that offer solutions for different applications and labs. These systems can analyze, separate and fractionate sample components based on size and molecular weight. 

AZURA® SEC is KNAUER's line of GPC and SEC systems that offer solutions for different applications and labs. These systems can analyze, separate and fractionate sample components based on size and molecular weight, making them useful for industries such as polymer, food, biochemistry, and pharmaceuticals, as well as research.The systems come in different variants, each tailored to specific lab needs, such as the AZURA SEC Compact for budget-friendly solutions or the &nbsp;Lab for highest analytical performance.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_AZURA_GPC_SEC_Systems_Application_areas_caaeb1284f.jpg" alt="KNAUER: AZURA GPC/SEC Systems - Application areas" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_AZURA_GPC_SEC_Systems_Application_areas_caaeb1284f.jpg 156w," sizes="100vw" width="1204" height="1204"><h3>GPC/SEC&nbsp; – Principles and parameters</h3><h4>Principle of GPC/SEC</h4><h5>How does GPC/SEC work?</h5>Gel Permeation Chromatography (GPC) and&nbsp;Size Exclusion Chromatography (SEC) separate&nbsp;analytes by size using special columns with a porous matrix. The basic separation principle relies on the fact that smaller molecules will be more likely to enter those pores, making their travel time through the matrix longer than that of larger molecules. Separations (typically of a mixture of polymers, polysaccharides or biomolecules) are facilitated by choosing optimal particle and pore sizes, as well as column length. GPC/SEC is often used in quality control and R&amp;D.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_AZURA_GPC_SEC_System_principle_gpc_00e63025c7.jpg" alt="KNAUER: AZURA GPC/SEC Systems - principle of GPC" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_AZURA_GPC_SEC_System_principle_gpc_00e63025c7.jpg 245w," sizes="100vw" width="648" height="232"><h4>GPC, SEC or GFC</h4><h5>Terminology in GPC/SEC</h5>Gel Permeation Chromatography (GPC), Size Exclusion Chromatography (SEC) and Gel Filtration Chromatography (GFC) &nbsp;all essentially describe the same methodology, but the term GPC tends to be used in polymer chemistry by those working with aggressive, organic solvents, while SEC and GFC are more commonly used by those separating biomolecules using aqueous solvents (buffers) or to reflect the use of aqueous buffers in polymer separations. Systems with organic solvents or aqueous-based solvents present some inherent challenges.The solvents used in polymer analysis are chosen for their ability to dissolve polymeric substances – and therefore may damage certain components of a device. And the use of salt buffers in SEC is harmful to metal components of the system. Hence, all liquid-contacting system components, from the valves and seals to tubing, must be carefully considered when developing such systems.<h4>What does GPC require?</h4><h5>What do I need for GPC?</h5>GPC columns are typically long and runs are performed at&nbsp;low flow rates of up to 1 ml/min and at low (&lt;100 bar) pressures. For the precise molecular weight determination, which is the goal of most GPC/SEC users, a good isocratic pump is essential for a steady baseline. Also a degasser suitable for a wide range of partly highly aggressive solvents is very important to ensure reproducible results. Additionally, temperature is crucial for many GPC applications so a thermostat to control the column temperature is essential.Due to the often very aggressive media used in polymer analysis, all wetted parts need to be compatible with the used solvent. Depending on the polymer it is important to keep this in mind when configuring a GPC system.<h4>What is GPC Cleanup?</h4>GPC Cleanup is a sample preparation method based on gel permeation chromatography (GPC). It is primarily employed for performing general cleanup tasks on a wide range of sample matrices such as foodstuffs, tissues, plants, and environmental samples. High-weight molecular substances, such as lipids, proteins, natural resins, cellular components, and steroids, interfering with subsequent analysis e.g. of pesticides are efficiently removed.<h3>Components for GPC/SEC systems</h3><h5>Columns</h5>Columns GPC/SEC separation efficiency is driven by long columns with large diameters, and the matrix is often based on porous silica or polymer material – the pore size determines the molecular weight range of the separation, and columns with different pore sizes are determines the molecular&nbsp; weight range of the separation, and columns with different pore sizes are combined to broaden separation and increase resolution.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_AZURA_GPC_SEC_System_Column_af59e0a074.jpg" alt="KNAUER: AZURA GPC/SEC Systems- Column" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_AZURA_GPC_SEC_System_Column_af59e0a074.jpg 245w," sizes="100vw" width="1280" height="699"><h5>Software</h5>The main goals are the determination of molar mass averages and the distribution of molar masses, which is performer through calibration using general standards with molar masses in a given range. Many chromatography data systems (CDS) are incapable of processing this data. With the GPC/SEC extension to our well-known ClarityChrom CDS software we offer our customers the possibility to continue working with a familiar software.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Knauer_Clarity_Chrom_Workstation_7ed6c2cb72.jpg" alt="Knauer: ClarityChrom Workstation" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Knauer_Clarity_Chrom_Workstation_7ed6c2cb72.jpg 245w," sizes="100vw" width="839" height="495"><h5>Extensions</h5>AZURA also affords customers the flexibility to extend their GPC/ SEC systems with autosamplers, valves, feed pumps, and column thermostats. In fact, many GPC runs are conducted at higher temperatures (&lt;60°C), so the AZURA column thermostat is of great interest.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Knauer_KNAUER_AZURA_Educational_HPLC_System_Column_selection_and_thermostat_567c35ab61.jpg" alt="KNAUER: AZURA GPC/SEC Systems - column thermostats" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Knauer_KNAUER_AZURA_Educational_HPLC_System_Column_selection_and_thermostat_567c35ab61.jpg 245w," sizes="100vw" width="1700" height="881"><h5>Pumps</h5>GPC/SEC analyses necessitate lower flow rates and lower pressure than HPLC. GPC/SEC runs are conducted isocratically, so a good isocratic pump is essential for a steady baseline. The AZURA excellent isocratic pump has been optimized to meet the requirements of GPC applications.Options:<ul><li>Normal phase</li><li>Aqueous eluents</li><li>Reversed phase pump with integrated solvent selection valve and degasser</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Knauer_High_pressure_gradient_HPLC_pump_AZURA_P_6_1_L_High_Pressure_Pump_with_10_ml_pump_head_stainless_steel_b7d7d07d6c.jpg" alt="Knauer: AZURA GPC/SEC Systems - pumps" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Knauer_High_pressure_gradient_HPLC_pump_AZURA_P_6_1_L_High_Pressure_Pump_with_10_ml_pump_head_stainless_steel_b7d7d07d6c.jpg 245w," sizes="100vw" width="1280" height="627"><h5>Detectors</h5>Our AZURA RI detector has been optimized for a better performance with organic solvents. Especially we have worked on significantly lower the drift with THF.Yu can alternatively choose between our UV/VIS detectors, variable single wavelength, multi- wavelength, or diode array.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_AZURA_GPC_SEC_System_AZURA_RID_2_1_2_13953c7ec5.jpg" alt="KNAUER: AZURA GPC/SEC Systems - RID 2.1 detector" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_AZURA_GPC_SEC_System_AZURA_RID_2_1_2_13953c7ec5.jpg 245w," sizes="100vw" width="1066" height="438">

KNAUER AZURA® Bio Compact SEC FPLC System

AZURA Compact SEC systems handle time-consuming SEC methods in your lab without occupying your valuable FPLC system.

KNAUER protein purification: The flexible FPLC platformAZURA® Bio purification systems&nbsp;complete solutions for FPLC on a minimum footprint: AZURA FPLC systems combine flexibility and reliability. The biocompatible/metal-free FPLC is the perfect choice for your protein purification task.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_AZURA_Bio_Compact_AC_FPLC_System_6_a874551078.jpg" alt="KNAUER: AZURA® Bio Compact AC FPLC System." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_AZURA_Bio_Compact_AC_FPLC_System_6_a874551078.jpg 245w," sizes="100vw" width="1506" height="600">Design your AZURA Bio purification system to fit your needs. Multiple functionalities such as automatic sample injection via autosampler, column switching, buffer and sample selection, and fraction collection enable automation of the purification process.A wide range of detectors ensures the visibility of target molecules. Various flow rates and compatibility with columns from all vendors provide maximum flexibility. The intuitive PurityChrom® software integrates all the advantages of a versatile purification system.<h3>AZURA® Bio Compact SEC FPLC System</h3><h4>For Size Exclusion Chromatography (SEC)</h4>AZURA Compact SEC systems take over time-consuming SEC methods in your lab without blocking your valuable FPLC system. Due to its compact design and intuitive FPLC software PurityChrom®, the system offers outstanding performance and ease of use.&nbsp;Pre-designed methods are included in the software for the designated SEC system and can be easily adapted by changing the column volume. AZURA Compact SEC supports all columns available on the market.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_AZURA_Bio_Compact_SEC_FPLC_System_4_f5efb08061.jpg" alt="KNAUER: AZURA® Bio Compact SEC FPLC System " srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_AZURA_Bio_Compact_SEC_FPLC_System_4_f5efb08061.jpg 245w," sizes="100vw" width="1358" height="540"><h3>Key features</h3><ul><li data-start="93" data-end="157">Flow rate: 0.001–10 ml/min (recommended: 0.1–8.0 ml/min)</li><li data-start="158" data-end="197">Maximum system pressure: 50 bar</li><li data-start="198" data-end="276">Injection system: Injection valve for sample injection via sample loop</li><li data-start="277" data-end="347">Detection: Variable single wavelength UV detector (190–500 nm)</li><li data-start="348" data-end="423">Fraction collection: Fraction collector for automated fractionation</li><li data-start="424" data-end="522">Column compatibility: Supports columns from all vendors, including third-party SEC columns</li><li data-start="523" data-end="611">Software: Intuitive and powerful PurityChrom® software, 21 CFR Part 11 compliant</li><li data-start="612" data-end="780">System design:<ul data-start="637" data-end="780"><li data-start="637" data-end="666">Isocratic buffer delivery</li><li data-start="669" data-end="687">Loop injection</li><li data-start="690" data-end="734">Wide range of collection racks available</li><li data-start="737" data-end="780">Specially designed for SEC applications</li></ul></li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_AZURA_Bio_Compact_SEC_FPLC_System_3_7a4bc1f60b.jpg" alt="KNAUER: AZURA® Bio Compact SEC FPLC System " srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_AZURA_Bio_Compact_SEC_FPLC_System_3_7a4bc1f60b.jpg 245w," sizes="100vw" width="1920" height="1152">Don't use your valuable gradient FPLC system for boring and time-consuming size exclusion separations. Choose your dedicated AZURA SEC system.<figure class="image"><img style="aspect-ratio:690/490;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_AZURA_Bio_Compact_SEC_FPLC_System_45d5079064.webp" alt="KNAUER: AZURA® Bio Compact SEC FPLC System." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_AZURA_Bio_Compact_SEC_FPLC_System_45d5079064.webp 220w," sizes="100vw" width="690" height="490"></figure>With its compact design and intuitive software, the system offers excellent performance, ease of use and supports all SEC columns available on the market.​

KNAUER AZURA® SEC Compact System

The AZURA SEC Compact systems provide excellent price-to-performance value, ideal for labs entering GPC/SEC, process control, or those with limited budgets and educational needs.

<h3>Compact, versatile system for SEC and GPC applications&nbsp;</h3>The AZURA SEC Compact systems offer an outstanding price-to-performance ratio and are the perfect solution for every laboratory entering the analytical world of GPC/SEC, for process control applications, or for limited-budget and educational laboratories.The heart of the systems is the Assistant ASM 2.2L is a docking station for three compact devices. Valves, pumps and UV detectors can be combined in one housing. Routine maintenance work e.g. replacing the lamp of a detector is easily performed by the user.Thanks to its modular concept the systems can be extended with additional components at any time later.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_AZURA_SEC_Compact_System_3_313d153f48.jpg" alt="KNAUER: AZURA® SEC Compact System." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_AZURA_SEC_Compact_System_3_313d153f48.jpg 237w," sizes="100vw" width="1009" height="664"><h3 data-start="857" data-end="879">Key Features</h3><ul data-start="880" data-end="1168"><li data-start="880" data-end="914">Flow rate: 0.001–10 ml/min</li><li data-start="915" data-end="946">Pressure: Up to 400 bar</li><li data-start="947" data-end="997">Intuitive operation with maximum precision</li><li>Injection via valve drive for minimal pressure spikes</li><li data-start="1043" data-end="1095">Supports a wide range of SEC and GPC columns</li><li data-start="1096" data-end="1128">Dedicated SEC/GPC ClarityChrom® add-on for in-depth data evaluation</li><li data-start="1129" data-end="1168">Expandable, space-saving design</li><li data-start="1129" data-end="1168">Suitable for organic and aqueous eluents</li></ul><h3 data-start="1175" data-end="1219">System Components &amp; Configurations</h3><ul data-start="1220" data-end="1486"><li data-start="1220" data-end="1242">Isocratic pump</li><li data-start="1243" data-end="1270">UV and RI detectors</li><li data-start="1271" data-end="1296">Column thermostat</li><li data-start="1297" data-end="1335">Automatic injection (optional)</li><li data-start="1336" data-end="1393">ClarityChrom® add-on for in-depth data evaluation</li><li data-start="1394" data-end="1486">Choose a hardware version for aqueous SEC of biomolecules or organic GPC of polymers</li></ul><h3 data-start="1493" data-end="1520">Detection Options</h3><ul data-start="1521" data-end="1555"><li data-start="1521" data-end="1555">RI, UV, ELSD, PDA, FLD, MS</li></ul><h3 data-start="1562" data-end="1587">Upgrade Options</h3><ul data-start="1588" data-end="1745"><li data-start="1588" data-end="1649">Automatic solvent recycle valve (cost-saving feature)</li><li data-start="1650" data-end="1666">Degasser</li><li data-start="1667" data-end="1686">Autosampler</li><li data-start="1687" data-end="1745">Additional detectors (RI, UV, ELSD, PDA, FLD, ECD)</li></ul>&nbsp;<figure class="image"><img style="aspect-ratio:1886/1452;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_AZURA_SEC_Compact_System_3c56c6482f.webp" alt="KNAUER: AZURA® SEC Compact System." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_AZURA_SEC_Compact_System_3c56c6482f.webp 203w," sizes="100vw" width="1886" height="1452"></figure>

KNAUER AZURA® SEC Lab System

The AZURA SEC Lab systems are ideal for labs requiring top analytical performance, offering unmatched flow precision and ultra-low pulsation for exceptional retention volume accuracy and reproducibility.

<h3>Highest analytical performance and robustness for SEC and GPC applications</h3>The AZURA SEC Lab systems are the perfect choice for laboratories that demands highest analytical performance. The system shows unsurpassed flow precision paired with ultra-low pulsation for outstanding retention volume precision and reproducibility.The autosampler can inject from up to 768 positions via microtiter plates or 108 standard 1.5 ml sample vials and is therefore the perfect choice for larger sample amount as well as for high sample throughput laboratories. Thanks to the reliable and robust design it is the workhorse in any laboratory.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_AZURA_SEC_Lab_System_e161ecef84.webp" alt="KNAUER: AZURA® SEC Lab System." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_AZURA_SEC_Lab_System_e161ecef84.webp 203w," sizes="100vw" width="1886" height="1452"><h3>Key Features</h3><ul><li>Injection volume: 1 –1000 µl&nbsp;</li><li>Easy maintenance</li><li>Great selection of SEC/GPC columns</li><li>Unsurpassed flow precision paired with ultra-low pulsation for</li><li>Highest analytical performance</li><li>Suitable for organic and aqueous eluents</li><li>Highest level of automation</li><li>Choose the matching hardware version for aqueous SEC of biomolecules or organic GPC of polymers</li></ul><h3>Upgrade Options</h3><ul><li>Save operating costs with an automatic solvent recycle valve</li><li>Degasser</li><li>Detector (RI, UV, ELSD, PDA, FLD, ECD)</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_AZURA_SEC_Lab_System_2_2cbe13a95d.webp" alt="KNAUER: AZURA® SEC Lab System." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_AZURA_SEC_Lab_System_2_2cbe13a95d.webp 234w," sizes="100vw" width="953" height="635"> All wetted parts are available in either bioinert materials or for standard phase solvents.

Products focused on GPC/SEC distributed by KNAUER - page 2

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