Meeting EU Drinking Water Standards: The Critical Role of Sample Prep in Trace Contaminant Analysis

<h3>Charged for Action: The Hidden Secrets of AEX Oligonucleotide Analysis</h3>Oligonucleotides—short, well-defined fragments of DNA or RNA—have become indispensable tools in modern life sciences. They underpin cutting-edge applications in molecular diagnostics, gene therapy, and pharmaceutical development. Before oligonucleotides can be confidently used in research or clinical settings, however, their quality must be rigorously assessed. Purity, sequence integrity, length distribution, and chemical modifications all play a decisive role in their performance.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Oligos_Made_Easy_Part_2_AEX_2_45eee54fa0.jpg" alt="KNAUER: Oligos Made Easy - Part 2: AEX" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Oligos_Made_Easy_Part_2_AEX_2_45eee54fa0.jpg 245w," sizes="100vw" width="1534" height="711">Among the analytical techniques available today, anion exchange chromatography (AEX) stands out as a robust and highly informative method for characterizing oligonucleotides. By exploiting their intrinsic negative charge, AEX provides detailed insight into product composition and impurity profiles that are difficult to obtain by other approaches.<blockquote><a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/article/6808">Part 1 of the Oligos series: A Practical Guide to Oligonucleotide Production – From Concept to Final Product</a></blockquote><h4>How Scientists Read Oligonucleotides Using Charge</h4>At the core of AEX lies a simple but powerful principle: oligonucleotides carry a negatively charged phosphate backbone. This charge increases in a predictable way with strand length and, to a lesser extent, sequence composition. Anion exchange chromatography uses this property to separate oligonucleotides based on differences in charge strength and interaction with a positively charged stationary phase.As a result, AEX has become one of the most widely used analytical tools for evaluating oligonucleotide quality. It allows scientists to distinguish full-length products from truncated species, degradation products, or closely related variants—often with single-nucleotide resolution.<h4>Why Ion Exchange Works: Binding, Retention, and Release</h4>Ion exchange chromatography (IEX) relies on electrostatic interactions between analytes and a charged stationary phase. In the case of oligonucleotides, anion exchange is used, where negatively charged molecules interact with positively charged functional groups on the resin—most commonly quaternary amines.The system consists of two main components:<ul><li>Stationary phase: A positively charged resin that binds anionic analytes.</li><li>Mobile phase: An aqueous buffer system, typically combined with a salt gradient, that controls both pH and elution strength.</li></ul>Retention in AEX is governed primarily by charge. Molecules with weaker overall charge interact less strongly with the stationary phase and elute earlier, while more highly charged oligonucleotides bind more tightly and require stronger elution conditions.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Oligos_Made_Easy_Part_2_AEX_Figure_1_IEX_overview_including_elution_order_dependency_on_analyte_charge_3419ad3075.jpg" alt="KNAUER: Oligos Made Easy - Part 2 AEX: Figure 1 IEX overview including elution order dependency on analyte charge." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Oligos_Made_Easy_Part_2_AEX_Figure_1_IEX_overview_including_elution_order_dependency_on_analyte_charge_3419ad3075.jpg 245w," sizes="100vw" width="1583" height="654"><h4>The Five-Step Workflow of Ion Exchange Chromatography</h4>AEX separations generally follow a well-established sequence of steps:<ol><li>Column equilibration The column is conditioned with the starting buffer until the baseline and pH are stable. This ensures that all charged sites on the resin are ready for interaction.</li><li>Sample loading Samples, prepared in the starting buffer, are introduced under conditions that promote binding of the target oligonucleotides while minimizing retention of unwanted impurities.</li><li>Washing The column is washed with the starting buffer to remove uncharged or weakly interacting components. The baseline stabilizes as these species are flushed away.</li><li>Elution Bound oligonucleotides are released using a salt or pH gradient. Increasing ionic strength introduces competing ions that displace the analytes from the resin. Weakly bound species elute first; strongly charged oligonucleotides elute later.</li><li>Regeneration and re-equilibration A high-salt buffer removes any remaining bound material. The column is then returned to starting conditions in preparation for the next analysis.</li></ol><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Oligos_Made_Easy_Part_2_AEX_Figure_2_Five_steps_of_IEX_procedure_in_blue_outlined_using_an_example_chromatogram_in_red_38dd70b1b1.jpg" alt="KNAUER: Oligos Made Easy - Part 2 AEX: Figure 2 Five steps of IEX procedure (in blue), outlined using an example chromatogram (in red)." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Oligos_Made_Easy_Part_2_AEX_Figure_2_Five_steps_of_IEX_procedure_in_blue_outlined_using_an_example_chromatogram_in_red_38dd70b1b1.jpg 245w," sizes="100vw" width="1583" height="674"><h4>Why AEX Is Especially Effective for Oligonucleotides</h4>The repeating phosphate backbone of oligonucleotides gives rise to a strong and uniform anionic character across a wide pH range (typically pH 7–9). This makes oligonucleotides exceptionally well suited for anion exchange separations.Key factors influencing AEX behavior include:<ul><li>Charge density: Longer oligonucleotides carry more negative charges and therefore exhibit stronger retention.</li><li>Resin chemistry: Strong and weak anion exchangers differ in functional groups and pH stability, influencing selectivity and robustness.</li><li>Buffer composition: The choice of buffering ions and salt gradients directly affects elution strength and resolution.</li></ul>Salt gradients—commonly based on chloride ions—compete with the oligonucleotide backbone for binding sites on the resin. By carefully tuning gradient slope and composition, analysts can achieve highly reproducible and finely resolved separations.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Oligos_Made_Easy_Part_2_AEX_Figure_3_Ionic_interactions_and_p_H_influence_on_Anion_Exchange_Chromatography_AEX_612e231ba4.jpg" alt="KNAUER: Oligos Made Easy - Part 2 AEX: Figure 3 Ionic interactions and pH influence on Anion Exchange Chromatography (AEX)." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Oligos_Made_Easy_Part_2_AEX_Figure_3_Ionic_interactions_and_p_H_influence_on_Anion_Exchange_Chromatography_AEX_612e231ba4.jpg 245w," sizes="100vw" width="1547" height="593"><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Oligos_Made_Easy_Part_2_AEX_Figure_4_AEX_buffer_selection_and_gradient_strategy_chromatogram_with_red_buffer_gradient_curve_53fd1bb11b.jpg" alt="KNAUER: Oligos Made Easy - Part 2 AEX: Figure 4 AEX buffer selection and gradient strategy (chromatogram with red buffer gradient curve)." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Oligos_Made_Easy_Part_2_AEX_Figure_4_AEX_buffer_selection_and_gradient_strategy_chromatogram_with_red_buffer_gradient_curve_53fd1bb11b.jpg 245w," sizes="100vw" width="1600" height="327"><h4>AEX as the Gold Standard for Oligonucleotide Separation</h4>Anion exchange chromatography has become the method of choice for both analytical and preparative oligonucleotide workflows. Its advantages include:<ul><li>High resolving power: Closely related impurities, including n–1 or n–2 species, can often be separated and quantified.</li><li>Predictable retention behavior: In many cases, retention time correlates linearly with oligonucleotide length, simplifying identification.</li><li>Compatibility with modified oligonucleotides: Even chemically modified sequences retain their anionic nature, allowing AEX to resolve both products and related impurities.</li><li>Excellent control via gradient elution: Salt gradients provide precise tuning of selectivity and resolution.</li></ul>Typically, shorter or degraded oligonucleotides elute at lower ionic strength, while full-length products with higher charge density appear later in the chromatogram.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/KNAUER_Oligos_Made_Easy_Part_2_AEX_Figure_5_AEX_Advantages_and_Challenges_7835521e34.jpg" alt="KNAUER: Oligos Made Easy - Part 2 AEX: Figure 5 AEX Advantages and Challenges." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_KNAUER_Oligos_Made_Easy_Part_2_AEX_Figure_5_AEX_Advantages_and_Challenges_7835521e34.jpg 245w," sizes="100vw" width="1535" height="707"><h4>Final Perspective: Mastering AEX with Confidence</h4>Anion exchange chromatography may appear complex at first, but with thoughtful optimization of pH, buffer composition, and gradient conditions, it becomes a highly precise and reliable tool for oligonucleotide analysis. When properly applied, AEX delivers sharp peaks, excellent resolution, and robust performance—even for challenging sequences and modifications.For laboratories developing or refining oligonucleotide workflows, AEX offers both analytical depth and operational confidence.<blockquote>If you would like to discuss AEX method development or optimization for oligonucleotides, feel free to contact us at sales@knauer.net. More insights into practical oligonucleotide analysis will follow in our “Oligos Made Easy” series.For technical questions or in-depth discussion, the author can be reached at kindler@knauer.net</blockquote>

Oligos Made Easy - Part 2: AEX

Although modern agriculture needs to be based on accurate real-time data on soil, plant, and environmental conditions, affordable, sufficiently sensitive, and robust monitoring devices for this purpose are currently missing. According to scientists, low-cost sensors based on new smart materials and printing technologies offer a suitable solution. The results of multidisciplinary research thus far and proposals for the development of these devices have been presented by researchers from Czechia, Great Britain, Spain, and the USA in a review article in the prestigious journal <a target="_blank" rel="noopener noreferrer" href="https://www.nature.com/articles/s41467-026-68778-6#Abs1">Nature Communications</a>.“Sensor technologies for monitoring plant health are still in their infancy. Only simple sensors capable of monitoring basic parameters such as pH, soil moisture, or temperature are commonly available on the market. However, if farmers are to face current challenges, including climate change, and ensure sufficient food for humanity, they need much more effective tools that will enable them to monitor, for example, various pathogens, including bacteria and fungi. In our opinion, a suitable solution is a combination of new smart materials and printing for the production of inexpensive, durable, and scalable materials,” said the article’s first author, David Panáček from CATRIN, who worked on the study during his internship at Imperial College London.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/CATRIN_Soucasne_senzory_nestaci_Vedci_navrhuji_novou_cestu_ke_sledovani_zdravi_rostlin_b4014952a3.jpg" alt="CATRIN: David Panáček" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_CATRIN_Soucasne_senzory_nestaci_Vedci_navrhuji_novou_cestu_ke_sledovani_zdravi_rostlin_b4014952a3.jpg 208w," sizes="100vw" width="1536" height="1152">Sensors for monitoring plant health, for example, lag behind similar devices used in human medicine. According to the authors, advances in materials science, which will enable the development of scalable sensor technologies, play a key role in this potential shift. “Printing techniques, including inkjet printing, screen printing, aerosol printing, 3D printing, and direct laser writing, offer flexible ways to produce flexible sensors, large-area sensors, and sensors integrated directly into plants. The review article summarizes recent advances in printable low-dimensional materials for agricultural sensors, analyzes their physico-chemical properties in relation to sensor performance, and discusses key challenges and future opportunities requiring interdisciplinary integration,” said one of the corresponding authors, Michal Otyepka.The research brought together materials scientists, chemists, biologists, sensing experts, and printing technology specialists. Materials research and the use of graphene-based smart materials were led by scientists from CATRIN at Palacký University and VŠB-Technical University of Ostrava. Plant biologists from CATRIN contributed their knowledge of plant development, their responses to stress conditions, and the monitoring of their properties. Researchers from Imperial College London took care of the electronics, while representatives from<a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/companies/36"> CEITEC – VUT</a> focused on printing technologies. The team also included leading experts in sensing from the Catalan Institute of Nanoscience and Nanotechnology in Barcelona, and Joseph Wang of the University of California San Diego, the “father of sensing and electrochemistry,” also contributed his extensive knowledge.“This is a groundbreaking study on this topic, which has managed to attract some truly big names in their respective fields. Last but not least, the study demonstrates that interdisciplinarity at CATRIN gives rise to completely new and promising research topics, such as plant sensing and its use for studying plant-environment interactions and smart agriculture,” added another corresponding author, Nuria De Diego.

Current sensors are not good enough. Scientists propose a new way to monitor plant health

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The Czech Advanced Technology and Research Institute (CATRIN) at Palacký University is a cutting-edge scientific hub dedicated to advancing research in the fields of nanotechnology, biotechnology, and biomedicine. At its core, CATRIN boasts outstanding scientific teams, featuring international researchers. We emphasize interdisciplinarity, foster global collaborations, and work to translate our research findings into practical applications.

CATRIN

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

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

ISTRAN EcaFlow Model 150 GLP automatic laboratory analyser

EcaFlow Model 150 GLP is a PC controlled automatic laboratory analyser for the determination of trace and high concentrations of metals, semi-metals and numerous nonmetals in various samples.

EcaFlow Model 150 GLP is a PC controlled automatic laboratory analyser for the determination of trace and high concentrations of metals, semi-metals and numerous nonmetals in various samples. By making use of the autosampler AS-150 up to 42 samples can be analysed in full automatic mode. The system supports the standardless, calibration curve and standard additions techniques. Over 70 validated applications are available for numerous sample types such as waters, foods, industrial liquids, wastes, etc. EcaFlow is a compact laboratory instrument controlled by a PC.<figure class="image"><img style="aspect-ratio:675/449;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ISTRAN_Eca_Flow_150_GLP_4_26c42795eb.jpg" alt="ISTRAN EcaFlow 150 GLP" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ISTRAN_Eca_Flow_150_GLP_4_26c42795eb.jpg 235w," sizes="100vw" width="675" height="449"></figure>The control unit contains the power support unit, control processor with a channel analyser, fast A/D and D/A converters and a high performance generic potentiostat/galvanostat. The compact flow system is controlled by the control unit and operates full automatically. It contains computer controlled electromagnetic valves for switching either to the sample solution or to an electrolyte solution or to a standard solution for the standard addition. Solutions are driven by a peristaltic pump. The heart of the system is the patented compact electrochemical cell.&nbsp;The cell uses disposable flow-through working electrodes made of suitable inert material. The counter and reference electrodes are separated from the flowing solutions hydrodynamically, so the reaction products at the counter electrode cannot interfere at the working electrode. The working electrode can be easily changed simply by loosening a screw. The cell is fixed to the panel of the instrument by a special connector which serves as an electrical contact to the electrodes. The connections of the tubes are made of Luer-type fitting, which facilitates fast manipulation when the electrode or cell is changed.<figure class="image"><img style="aspect-ratio:675/449;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ISTRAN_Eca_Flow_150_GLP_5_ac69cdfecf.jpg" alt="ISTRAN EcaFlow 150 GLP" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ISTRAN_Eca_Flow_150_GLP_5_ac69cdfecf.jpg 235w," sizes="100vw" width="675" height="449"></figure><h4>Technical data</h4>Potentiostat/galvanostat: 12 V / 20 mA Measuring cell: EcaCell 353c or EcaCell 104 with three electrodes Flow system: Full computer control with peristaltic pumping Weight: 7 kg Dimensions: 500 x 450 x 140 mm Software: Chronopotentiometry, coulometry, voltammetry Computer (option): Any PC with Windows XP and higher Autosampler (option): 42 positions + blank + standard<figure class="image"><img style="aspect-ratio:675/449;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ISTRAN_Eca_Flow_150_GLP_3_f4b61911c2.jpg" alt="ISTRAN EcaFlow 150 GLP" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ISTRAN_Eca_Flow_150_GLP_3_f4b61911c2.jpg 235w," sizes="100vw" width="675" height="449"></figure><h4>Available applications (all included):</h4><ol><li>Flow-through analyser test&nbsp;&nbsp;</li><li>Simultaneous determination of Cd, Pb and C&nbsp;</li><li>Determination of Pb&nbsp;</li><li>Simultaneous determination of Sn and Pb&nbsp;</li><li>Simultaneous determination of Pb, Cd and Hg&nbsp;</li><li>Determination of EDTA&nbsp;</li><li>Simultaneous determination of Zn, Cd, Pb, and Cu&nbsp;</li><li>Simultaneous determination of Cd, Pb, a Cu in wines&nbsp;</li><li>Determination of Ag&nbsp;</li><li>Determination of As(III) and total As in urine&nbsp;</li><li>Determination of As(III) and total As in fertilisers&nbsp;</li><li>Determination of Se in waters&nbsp;</li><li>Determination of Mn&nbsp;</li><li>Determination of Hg&nbsp;</li><li>Determination of Fe in waters&nbsp;</li><li>Determination of Sn&nbsp;</li><li>Determination of Bi&nbsp;</li><li>Determination of As in drugs&nbsp;</li><li>Determination of chlorides in waters&nbsp;</li><li>Simultaneous determination of Zn, Cd, Pb, and Cu in wines&nbsp;</li><li>Simultaneous determination of Zn, Cd, Pb, and Cu in spirits&nbsp;</li><li>Simultaneous determination of Cd, Pb, and Cu in beers&nbsp;</li><li>Determination of Fe (higher concentrations) in waters&nbsp;</li><li>Determination of Cd, Pb, and Cu in soil extracts&nbsp;</li><li>Determination of Sb&nbsp;</li><li>Simultaneous determination of Zn, Cd, Pb, and Cu in waters&nbsp;</li><li>Determination of As(III) and total As in waters&nbsp;</li><li>Determination of Zn, Cd, Pb, and Cu in pectines&nbsp;</li><li>Determination of iodides in urine&nbsp;</li><li>Determination of Au in water samples&nbsp;</li><li>Determination of low Ni contents&nbsp;</li><li>Determination of iodides in foods and beverages&nbsp;</li><li>Determination of Cr(VI) and total Cr in waters&nbsp;</li><li>Determination of nitrates in waters&nbsp;</li><li>Determination of Ascorbic Acid&nbsp;</li><li>Determination of chlorites in waters&nbsp;</li><li>Determination of bromates in waters&nbsp;</li><li>Boric acid in nickel plating baths&nbsp;</li><li>Determination of total As in waters&nbsp;</li><li>Acidimetry determination of strong and weak acids&nbsp;</li><li>Determination of Fe in concentrated sulphuric acid&nbsp;</li><li>Determination of Cu in waste waters&nbsp;</li><li>Alkalimetry determination of strong bases&nbsp;</li><li>Simultaneous determination of total As and Hg&nbsp;</li><li>Determination of Zn in galvanic baths&nbsp;</li><li>Determination of Ni in galvanic baths&nbsp;</li><li>Chlorides in galvanic baths&nbsp;</li><li>Cr(III) in passivating galvanic baths&nbsp;</li><li>Determination of phosphates with microporous electrodes&nbsp;</li><li>Determination of sub-ppb Hg concentrations&nbsp;</li><li>Determination of Zn in waste waters&nbsp;</li><li>Cu in wine samples&nbsp;</li><li>Determination of Fe in clear and turbid water samples&nbsp;</li><li>Determination of Au in ores&nbsp;</li><li>Determination of Sb in the presence of As and Cu&nbsp;</li><li>Determination of low Se concentrations&nbsp;</li><li>Sulphites in wines&nbsp;</li><li>Sulphites in beers&nbsp;</li><li>Titanium in TiO2&nbsp;</li><li>Determination of phosphates in clear as well as turbid water samples&nbsp;</li><li>Determination of total ammonia in underground and tap waters&nbsp;</li><li>Determination of total ammonia in waste waters&nbsp;</li><li>Determination of Cr(VI) in clear as well as turbid water samples&nbsp;</li><li>Determination of Ni in clear as well as turbid water samples&nbsp;</li><li>Determination of sulphides (S2-) in waste waters&nbsp;</li><li>Simultaneous determination of Zn, Cd, Pb, and Cu in turbid samples&nbsp;</li><li>Coulometric determination of sulphides in waters&nbsp;</li><li>Acid content in wines&nbsp;</li><li>Ethanol in beverages&nbsp;</li><li>Sulphites (SO3-) in foods&nbsp;</li><li>Chlorides (Cl-) in foods&nbsp;</li><li>Chlorites (ClO2-) in disinfected water&nbsp;</li><li>Manganese (Mn) in aquatic samples&nbsp;</li><li>Bromides (Br-) in water&nbsp;</li><li>Cd, Pb and Cu in concentrated zinc sulphate&nbsp;</li><li>Simultaneous determination of Pb, Cu and Hg in water</li></ol>

ISTRAN PCA2 Portable coulometric analyser

The new Portable Coulometric Analyser PCA is designed for laboratory and field analysis of heavy metals, semi-metals and numerous non-metals in aquatic solutions for a broad concentration range addressing contents from sub-μg/L up to several g/L.

The new Portable Coulometric Analyser PCA is designed for laboratory and field analysis of heavy metals, semi-metals and numerous non-metals in aquatic solutions for a broad concentration range addressing contents from sub-μg/L up to several g/L. In battery operation mode it is well suited for field applications. The analysis is full automatic, the sample solution is transported to the electrochemical measuring cell by means of a small but robust peristaltic pump and on completing the analysis the result is displayed and stored in the memory. The human interface is a simple touch screen.<h3>APPLICATION FIELDS</h3><ul><li>Drinking water</li><li>Surface water</li><li>Waste water</li><li>Foods and beverages</li><li>Biological samples</li></ul><figure class="image"><img style="aspect-ratio:1116/324;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ISTRAN_PCA_2_Portable_coulometric_analyser_aae89cc7dc.jpg" alt="ISTRAN PCA2 Portable coulometric analyser" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ISTRAN_PCA_2_Portable_coulometric_analyser_aae89cc7dc.jpg 245w," sizes="100vw" width="1116" height="324"></figure><h3>UNIQUE FEATURES</h3><ul><li>Metals, semi-metals, non-metals</li><li>Robust portable design</li><li>Full automatic analysis</li><li>At least 12 hours on battery operation ideal for field applications</li><li>Simple and fast operation</li><li>Ready to use applications</li><li>Broad concentration range, starting at sub-μg/L</li><li>Also suitable for coloured and turbid samples</li></ul><h3>TYPICAL APPLICATIONS INCLUDE</h3><ul><li>Arsenic, antimony, tin and selenium in various water samples</li><li>Heavy metals such as mercury, thallium, cadmium, indium, lead, bismuth, silver, gold.</li><li>Manganese, iron, cobalt, nickel, copper, zinc, gallium in various water samples</li><li>Chromium(VI) and total chromium</li><li>Iron(II), iron(III), total iron</li><li>Arsenic(III) and total arsenic</li><li>C-vitamin in vegetables, fruits, beverages, foods</li><li>Fluoride, chloride, bromide, iodide in waters and biological samples</li><li>Disinfection reagents such as chlorine, chlorine dioxide, hypochlorite in drinking water</li><li>Disinfection by-products such as chlorite, bromate in drinking water</li><li>Sulphite in foods, wines and beers</li><li>Sulphides in waste waters</li><li>Ammonia, hydrazine, nitrite, nitrate, cyanide in aquatic samples</li><li>Phosphate in waste waters</li><li>Ethanol in beverages</li><li>Methanol in waste water</li><li>Acids and bases in aquatic solutions, wines</li><li>Samples with suspended particles and solid samples can be analysed after an appropriate sample digestion, e.g. thermal, UV or microwave-assisted sample digestion.</li></ul>Ag, Ammonia, As, Bromate, Bromide, Cd, Chloride, Chlorite, Co, Cr(VI), Cu, EDTA, Fe, Hg, Iodide, Mn, Ni, Nitrite, Pb, Sb, Se, Sn, Sulphide, Tl, Zn<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Screenshot_2025_03_21_at_12_33_28_Istran_2_2d3350cbc8.jpg" alt="ISTRAN PCA2 Portable coulometric analyser" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Screenshot_2025_03_21_at_12_33_28_Istran_2_2d3350cbc8.jpg 245w," sizes="100vw" width="1116" height="326"><h3>ANALYSIS PRINCIPLE</h3>The analysis is based on automatic flow-through coulometry and voltammetry making use of a unique robust electrochemical measuring cell with a maintenance-free built-in reference and auxiliary electrodes and a long-life disposable working electrode. The sample solution is pumped into the cell where the determined species (analyte) is measured through its electrochemical conversion, i.e. it is electrochemically oxidised or reduced at the electrode surface. Low concentrations are determined after a preliminary electrochemical deposition of the measured species at the electrode surface (enrichment step), then the deposit is stripped by constant current while the signal is recorded and evaluated. In such a way, concentrations in the sub- μg/L level can be easily measured. A typical response of copper displayed on the touchscreen is depicted below.<figure class="image"><img style="aspect-ratio:1116/326;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ISTRAN_PCA_2_Portable_coulometric_analyser_3_d630e0cd53.jpg" alt="ISTRAN PCA2 Portable coulometric analyser: A typical response of copper displayed on the touchscreen" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ISTRAN_PCA_2_Portable_coulometric_analyser_3_d630e0cd53.jpg 245w," sizes="100vw" width="1116" height="326"></figure><h4>The analytical procedure consists of three main steps:</h4><ol><li>Sample preparation. It includes the filtration of the sample (when necessary) and addition of a reagent to the sample. Solid samples or samples with suspended particles require a sample digestion..</li><li>Analysis. Full automatic procedure yielding the result displayed on the touch screen. The analysis starts on immersing the sampling tube into the sample which is pumped through the measuring cell where the analyte is electrochemically measured. Usually multiple runs are done with measurements repeated and evaluated automatically.</li><li>Cleaning. On completion of the analyses the cell is rinsed with water or a suitable reagent solution and the analyser is set to standby mode or turned down.</li></ol><h3>CONTROL AND COMMUNICATION</h3><ul><li>User interface: Powerful 4.3” Intelligent LCD-TFT display module. 480 x 272 Resolution, RGB 65K true to life colours, TFT Screen with integrated 4-wire Resistive Touch Panel. On-board micro-SD memory card connector for data logging purposes</li><li>User interface for uploading new measuring parameters, downloading results and curves</li><li>User interface with administrator access, firmware upgrading and calibration of electronic circuits</li></ul><h3>MECHANICAL AND ELECTRICAL DATA</h3><ul><li>Enclosure: The PCA instrument is integrated into a robust transport case made of polypropylene. Watertight, crushproof, and dustproof. Protection class IP 67</li><li>Dimensions (W x D x H): 27 x 24.6 x 12.4 cm (10.62” x 9.68” x 4.87”)</li><li>Weight: 2.9 kg (6.4 lbs)</li><li>Power input: 100-240V/50-60Hz&nbsp;</li><li>Battery: Ni-MH, 14.4V/4.5Ah</li><li>Ambient operating conditions: 5 °C – 45 °C at 5 - 95% relative humidity non-condensing (41 °F – 113 °F)</li></ul><h3>TECHNICAL SPECIFICATIONS</h3><h4>MEASUREMENT</h4><ul><li>Analysis method: Coulometry and voltammetry in chronopotentiometric mode</li><li>Determined species: Metals, semi-metals, non-metals, organics (refer to the up to date list of applications)</li><li>Measuring cell: robust three-electrode flow-through cell. Built-in maintenance-free platinum auxiliary and silver/silver chloride reference electrodes. Longlife disposable working electrodes made of glassy carbon, gold, silver, platinum, copper. No mercury or gold plating solutions required.</li><li>Detection limit: less than 1 μg/L *</li><li>Precision (RSD, under repeatability conditions): 5 % full scale for calibration or validation solutions</li><li>Calibration: A built-in 10 point calibration curve adjusted in the factory</li><li>Re-calibration: Two point re-calibration (blank and calibration solution) carried out on demand</li><li>Measuring ranges: Please check the respective application list for each parameter</li><li>Analysis time/run: 1-10 min, depending on the analyte concentration *.</li></ul>*Refer to the corresponding application list<h4>DATA LOGGING AND SECURITY</h4><ul><li>Log files with over 1000 results and corresponding curves are stored</li><li>Easy export to spreadsheet files</li></ul><h4>GLP FEATURES</h4><ul><li>Automatic storage of about 1000 results, including the corresponding signal curve, date, time of analysis and the sample identifier.</li><li>Statistical evaluation of the results</li><li>Checking the accuracy and precision by means of a control sample with known analyte concentration.</li></ul><figure class="image"><img style="aspect-ratio:1116/326;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ISTRAN_PCA_2_Portable_coulometric_analyser_4_6b3bf1dde1.jpg" alt="ISTRAN PCA2 Portable coulometric analyser " srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ISTRAN_PCA_2_Portable_coulometric_analyser_4_6b3bf1dde1.jpg 245w," sizes="100vw" width="1116" height="326"></figure><h4>REAGENTS AND CONSUMABLES</h4><ul><li>Reagents, consumables, containers and tools can be transported in a separate transport case</li><li>Reagent consumption is low, usually 0.1 to 1 mL/sample</li><li>No organic or toxic reagents are used</li><li>All reagents and consumables are delivered by the producer</li><li>Reagent formulas are available against royalties</li><li>Cleaning solution: Demineralised water or in most cases tap water is sufficient</li><li>Calibration or validation solution: Available from the producer, prepared from single element Certified Reference Materials</li></ul><h4>OPTIONS</h4><ul><li>Additional applications each including a measurement parameter file, measuring cell (if needed), electrode</li><li>Transport case for reagents, consumables, tools ideal for field operation</li></ul>

ISTRAN EcaLayer Metal Layer Analyser

The coulometric method ensures accurate and precise results. The analyser is extremely simple to use and therefore it is also suitable for routine measurements not needing any special qualification.

The coulometric technique is used for measuring the thickness of electroplated deposits on a wide variety of substrates such as steel, aluminium, copper, nickel, silver, alloys, some insulators.The coulometric method ensures accurate and precise results. The analyser is extremely simple to use and therefore it is also suitable for routine measurements not needing any special qualification. Moreover, coulometry is the only method allowing the measurement of multi-layer coatings such as chrome, chrome oxide on tin, tin, tin-iron intermetals on steel, etc.<h3>Measuring principle</h3>The fundamental principle is the Faraday’s Law. The method is similar to the electrolytic plating process but here the coating is removed electrochemically from a defined surface area. For this purpose, a piece of the sample is placed to the flow-through measuring cell which is filled with a suitable electrolyte solution and the analysed metal coating is subsequently removed by applying an appropriate current. Hence, metal layers are measured by anodic dissolution, metal oxide layers, such as tin oxide on a tin coating, are measured by cathodic dissolution. The measured sample area is given by the gasket used and it can include 0.2 to 20 cm2. The analysis is performed totally automatically and is controlled by a PC.By applying the Faraday’s Laws, the thickness of a metal layer can be calculated.<h3>The EcaLayer Model 220/220a consists of three major parts:</h3><figure class="image"><img style="aspect-ratio:643/961;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ISTRAN_Eca_Layer_Metal_Layer_Analyser_4_ab4b7f6aff.jpg" alt="ISTRAN EcaLayer Metal Layer Analyser - Scheme" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ISTRAN_Eca_Layer_Metal_Layer_Analyser_4_ab4b7f6aff.jpg 104w," sizes="100vw" width="643" height="961"></figure><h4>1. Analytical Unit</h4><h5>Two types of analytical units can be used:</h5><ul><li>Module A for metal coatings and metal oxide layer measurements needing the removal of dissolved oxygen, e.g. tin oxide measurements, and</li><li>Module B for measurements not needing oxygen removal, e.g. tin layer thickness measurements.</li></ul>Module A encloses a unique flow-through analytical cell with the sample as the working electrode, a stainless steel counter and Ag/AgCl reference electrodes, a peristaltic pump, an electromagnetic valve for the gas and a reservoir for the electrolyte solution.Module B is built in the same way but without the gas unit.<h4>2. Control Unit</h4>The control unit comprises a computer controlled potentiostat/galvanostat with a maximum output of 100 mA, 16-bit A/D and D/A converters. The unit is controlled by a microprocessor linked to the PC through a serial line.<h4>3. Computer and software</h4>Any IBM compatible PC can be coupled to the instrument. The user-friendly software facilitates the use without any special knowledge about electrochermistry. GLP facilities such as archiving, printing of reports, selftesting are included.<h3>Function</h3><h4>The metal layer analyser works as follows:</h4><ol><li>The sample is placed into the cell and the cell is closed. The next steps are performed automatically by computer control.</li><li>The cell is filled with the electrolyte from the reservoir. If needed, the electrolyte solution is with an inert gas to remove dissolved oxygen.</li><li>The coating is removed by applying a suitable constant current and the potential of the sample material (i.e. the working electrode) is monitored and registered in the time.</li><li>The electrolyte solution is removed from the cell.</li><li>In the meantime, the registered potential-time dependence is evaluated giving the dissolution time and the layer thickness is calculated automatically.</li><li>The cell is opened and the sample is removed. The whole procedure takes 4 to 8 minutes.</li></ol><h3>Some applications</h3><h5>Measurements of tin coatings on steel</h5>Tin coatings are measured by anodic dissolution in HCl electrolyte solution with currents up to 100 mA. Both the tin and the tin-iron intermetallic layers can be measured in a single run.<figure class="image"><img style="aspect-ratio:621/342;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ISTRAN_Eca_Layer_Metal_Layer_Analyser_0d2f857bae.jpg" alt="ISTRAN EcaLayer Metal Layer Analyser: Measurements of tin coatings on steel" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ISTRAN_Eca_Layer_Metal_Layer_Analyser_0d2f857bae.jpg 245w," sizes="100vw" width="621" height="342"></figure><h5>Measurement of passivating chromous layers on tin coated steel</h5>The chromium layers are dissolved by anodic oxidation in a phosphate buffer electrolyte solution with currents of few mA.<figure class="image"><img style="aspect-ratio:645/353;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ISTRAN_Eca_Layer_Metal_Layer_Analyser_2_31bc2b54d5.jpg" alt="ISTRAN EcaLayer Metal Layer Analyser: Measurement of passivating chromous layers on tin coated steel" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ISTRAN_Eca_Layer_Metal_Layer_Analyser_2_31bc2b54d5.jpg 245w," sizes="100vw" width="645" height="353"></figure><h5>Measurement of oxide layers on tin coatings</h5>Oxide layers can be determined by cathodic dissolution in deairated HBr electrolyte solution with currents about -1 mA. Due to the uncertain stoichiometry of the oxide layers, the results are expressed as charge consumed per sample area.<figure class="image"><img style="aspect-ratio:685/348;" src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ISTRAN_Eca_Layer_Metal_Layer_Analyser_3_0b111ab468.jpg" alt="ISTRAN EcaLayer Metal Layer Analyser: Measurement of oxide layers on tin coatings" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ISTRAN_Eca_Layer_Metal_Layer_Analyser_3_0b111ab468.jpg 245w," sizes="100vw" width="685" height="348"></figure><h3>Ordering information</h3><h5>EcaLayer Model 220 includes</h5><ul><li>Control Unit</li><li>Flow System with Module A</li><li>Application software</li><li>PC with printer (specified by the customer)</li><li>All necessary cables</li><li>Users manual</li><li>Methodologies according to EN ISO 2177</li></ul><h5>EcaLayer Model 220a includes</h5><ul><li>Control Unit</li><li>Flow System with Module B</li><li>Application software</li><li>PC with printer (specified by the customer)</li><li>All necessary cables</li><li>Users manual</li><li>Methodologies according to EN ISO 2177</li></ul>

Products from category Electroanalytical methods focused on Electrochemistry - page 1

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