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

Thermo Scientific Dionex IonPac AS23 IC Columns

Measure trace bromate and other oxyhalides in drinking water, ground water with Thermo Scientific Dionex IonPac AS23 carbonate eluent anion-exchange column. 

Measure trace bromate and other oxyhalides in drinking water, ground water, wastewater, and other diverse sample matrices with the Thermo Scientific™ Dionex™ IonPac™ AS23 carbonate eluent anion-exchange column. The column is specifically designed and recommended for the determination of trace bromate, a toxic byproduct of ozone disinfection, in drinking water matrices. The column's high capacity and selectivity facilitate the determination of bromate in drinking water at the low-μg/L level in the presence of high concentration of chloride, sulfate and carbonate. The Dionex IonPac AS23 columns meet the performance requirements of U.S. EPA Methods 300.0 and 300.1.<h5>Analysis of Trace Level Bromate in Drinking Water</h5><ul><li>Compliance monitoring of common anions and oxyhalides in drinking water as specified in U.S. EPA Method 300.0 and 300.1</li><li>Simple analysis of trace bromate in drinking water matrices using an isocratic carbonate/bicarbonate eluent with suppressed conductivity detection</li><li>Optimized selectivity to ensure low ppb determination of bromate in the presence of very high concentrations of chloride, sulfate, and carbonate</li><li>Separates oxyhalides and common inorganic anions in drinking water, groundwater, wastewater and other diverse sample matrices</li><li>High capacity for the analysis of most drinking water without the use of sample pretreatment or preconcentration</li><li>Solvent compatibility for easy column cleanup after the analysis of samples with hydrophobic components</li></ul><h5>Multiple Formats Available for Application Flexibility</h5><ul><li>4x250mm, 2x250mm analytical columns</li><li>4x50mm, 2x50mm guard columns</li><li>Longer 250mm columns facilitate higher resolution separations of more complex sample matrices</li><li>Smaller i.d. columns provide higher mass sensitivity, eluent and reagent conservation and lower operating costs</li></ul>Note: For simple, accurate eluent preparation, use the Dionex IonPac AS23 Eluent Concentrate.<h4>Specifications</h4><ul><li>Anion Exchange Capacity: 320 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 320 μeq</li><li>Column Chemistry: Carbonate/Bicarbonate</li><li>For Use With (Application): Anion Exchange</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 3000 psi (207 bar)</li><li>Solvent Compatibility: 0 to 100% HPLC Solvents</li><li>Stationary phase: IonPac AS23</li><li>Format: Standard Bore</li><li>Packing Material: Polymeric</li></ul>

Thermo Scientific Dionex IonPac AS27 IC Columns

Achieve high resolution separations of trace oxyhalides and inorganic anions in drinking water using Thermo Scientific Dionex IonPac AS27 Analytical and Guard columns.

Achieve high resolution separations of trace oxyhalides and inorganic anions in drinking water using Thermo Scientific™ Dionex™ IonPac™ AS27 Analytical and Guard columns. These hydroxide-selective anion-exchange columns allows analysis of most drinking water preserved with ethylenediamine (EDA) without sample pretreatment or preconcentration. The Dionex IonPac AS27 columns meets the performance requirements of US EPA Methods 300.0 and 300.1.<h5>Analyzes Oxyhalides and Inorganic Anions in Drinking Water</h5><ul><li>Optimized for analysis of trace bromate in drinking water preserved with EDA</li><li>High capcity: 220μeq per column (4x250mm)</li><li>Meets or exceeds performance requirements of US EPA Methods 300.0 and 300.1</li><li>Column selectivity is optimized for 30°C operating temperature</li><li>Compatible with organic solvents</li></ul><h5>Choose from Multiple Formats for Application Flexibility</h5><ul><li>4x250mm, 2x250mm, 0.4x250mm analytical columns</li><li>4x50mm, 2x50mm, 0.4x50mm guard columns</li></ul><h4>Specifications</h4><ul><li>Anion Exchange Capacity: 220 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 220 μeq</li><li>Column Chemistry: Hydroxide</li><li>For Use With (Application): Anion Exchange</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 3000 psi (207 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% HPLC Solvents</li><li>Stationary phase: Super Macroporous Resin</li><li>Format: Standard Bore</li><li>Packing Material: Polymeric</li></ul>

Thermo Scientific Dionex IonPac AS28-Fast-4μm IC Columns

Analyze trace inorganic anions and low molecular weight organic acids using the Thermo Scientific Dionex IonPac AS28-Fast-4μm ion chromatography (IC) columns. 

Analyze trace inorganic anions and low molecular weight organic acids using the Thermo Scientific™ Dionex™ IonPac™ AS28-Fast-4μm ion chromatography (IC) columns. Designed specifically for trace level analysis of high purity water from semiconductor and power industries, this column combines the selectivity of the Thermo Scientific™ Dionex™ IonPac™ AS15 column, with fast, high efficiency, and high resolution separations. The Dionex IonPac AS28-Fast-4μm columns uses smaller 4μm resin particles for more efficient separations resulting in more accurate peak integration and more reliable results.<h5>Applications for Dionex IonPac AS28-Fast-4μm IC Columns</h5><ul><li>Separation of common anions and low molecular weight organic acids</li><li>For both high purity water matrices and complex matrices including chemical and petrochemical samples</li><li>Compatible with organic solvents to enhance analyte solubility, modify column selectivity, and facilitate effective column clean-up</li></ul><h5>Superior Performance</h5><ul><li>Improved efficiencies and resolution compared to the Dionex IonPac AS15 column</li><li>Easily transfer applications from the Dionex IonPac AS15 column to the AS28-Fast-4μm column due to the similar selectivity</li></ul><h5>For Use With a High-Pressure IC System</h5>Higher resolution is achieved through the use of smaller resin particles, which produce a column backpressure over 3000 psi at the standard flow rates. A high-pressure IC system, such as the Thermo Scientific™ Dionex™ ICS-5000+ HPIC™ or the Thermo Scientific Dionex ICS-4000 Capillary HPIC system is required to operate this column under standard conditions and take advantage of elevated flow rates and faster run times.<h5>Reduce Operating Costs With Lower Eluent Requirements</h5>The Dionex IonPac AS28-Fast-4μm capillary columns provide the same performance as the standard bore and microbore Dionex IonPac AS28-Fast-4μm columns because they are packed with the same material. Operating costs are reduced because the capillary system operates at only 1% of the eluent flow rate of the standard bore system, requiring less eluent and producing less waste.<h5>Multiple Formats Available</h5><ul><li>4 x 150mm and 2 x 150mm analytical columns</li><li>4 x 30mm and 2 x 30mm analytical guard columns</li><li>0.4 x 150mm capillary columns</li><li>0.4 x 35mm capillary guard columns</li><li>Smaller i.d. columns provide higher mass sensitivity, eluent and reagent conservation, and lower operating costs</li></ul><h4>Specifications</h4><ul><li>Anion Exchange Capacity: 230 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 230 μeq</li><li>Column Chemistry: Hydroxide</li><li>For Use With (Application): Anion Exchange</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 5000 psi (345 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% Acetonitrile, Methanol, and Isopropanol</li><li>Stationary phase: Super Macroporous Ethylvinylbenzene Polymer Cross-Linked with Divinylbenzene</li><li>Format: Standard Bore</li><li>Packing Material: Ethylvinylbenzene/Divinylbenzene</li></ul>

Thermo Scientific Dionex IonPac AS29-Fast-4μm IC Columns

Analyze inorganic anions in high ionic strength matrices using Thermo Scientific™ Dionex™ AS29-Fast-4μm ion chromatography (IC) columns.

Analyze inorganic anions in high ionic strength matrices using Thermo Scientific™ Dionex™ AS29-Fast-4μm ion chromatography (IC) columns. Specifically designed to handle high ionic strength samples, Dionex IonPac AS29-Fast-4μm columns can easily separate the common inorganic anions in less than 10 minutes and can tolerate samples with high or low pH without requiring any pretreatment. They are ideal for analzying drinking water, wastewater, process streams, and scrubber solutions. Use with the Dionex AS29 Eluent Concentrate for fast, convenient, and reliable eluent preparation.<h5>Fast separation of common inorganic anions with excellent resolution</h5><ul><li>Achieve fast, isocratic separation of common inorganic anions in less than 10 minutes.</li><li>Analyze high ionic strength samples without compromising the separation of other analytes.</li><li>Excellent resolution of carbonate away from the common inorganic anions.</li><li>Robust stationary phase can tolerate acidic or basic samples without the need for pretreatment.</li><li>Similar peak efficiency to Dionex IonPac AS22-Fast-4μm column with the same elution order.</li><li>Solvent compatibility permits easy column cleanup after the analysis of samples with hydrophobic components.</li><li>Use with Dionex AS29 Eluent Concentrate for simple and accurate eluent preparation.</li></ul><h5>Use with a High Pressure IC system</h5>Higher resolution is achieved through the use of smaller resin particles, which produce a column backpressure over 3000 psi at the standard flow rates. A high-pressure IC system, such as the Thermo Scientific™ Dionex™ ICS-5000+ HPIC™ system or Thermo Scientific™ Dionex™ Integrion™ HPIC system is required to operate this column under standard conditions.<h4>Specifications</h4><ul><li>Anion Exchange Capacity: 126 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 126 μeq</li><li>Column Chemistry: Carbonate/Bicarbonate</li><li>For Use With (Application): Anion Exchange</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 5000 psi (345 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% Organic HPLC Solvents</li><li>Stationary phase: Super Macroporous Resin</li><li>Format: Standard Bore</li><li>Packing Material: Ethylvinylbenzene/Divinylbenzene</li></ul>

Thermo Scientific Dionex IonPac AS30 IC Columns

Achieve high resolution separations of trace oxyhalides and inorganic anions in drinking water with Thermo Scientific Dionex IonPac AS30 columns.

Achieve high resolution separations of trace oxyhalides and inorganic anions in drinking water with Thermo Scientific™ Dionex™ IonPac™ AS30 columns. The column selectivity has been optimized for trace level analysis of bromate in drinking water preserved with ethylenediamine (EDA). EDA is used as a preservative in some drinking water samples and can cause interference with early eluting peaks. The high capacity of this hydroxide-selective anion-exchange column allows large loop injections for trace analysis (μg/L) without sample pre-treatment or preconcentration.<h5>Superior Chromatographic Performance</h5><ul><li>Optimized for analysis of trace bromate in drinking water preserved with EDA</li><li>High capacity: 477 μeq/column (4 x 250 mm) allows large loop injections for trace analysis</li><li>Column selectivity has been optimized at an operating temperature of 30°C</li><li>Compatible with organic solvents</li></ul><h5>Unique Selectivity for Samples Preserved with Ethylenediamine</h5>The selectivity of the Dionex IonPac AS30 column has been optimized to facilitate quantitation of trace levels of bromate in drinking water containing up to 50 ppm ethylenediamine (EDA). Ethylenediamine is sometimes added to drinking water samples as a preservative and can react with carbonate to produce artifacts that interfere with early eluting analytes such as fluoride. The Dionex IonPac AS30 column minimizes this interference by increasing the separation between fluoride and the EDA carbamate artifact, allowing better integration of the fluoride peak. In comparison to the Dionex IonPac AS19 and IonPac AS27 columns, the Dionex IonPac AS30 column features unique selectivity and much higher column capacity to enable separation of fluoride from the EDA carbamate artifact as well as separation of carbonate and sulfate for better quantification of sulfate.The Dionex IonPac AS30 column is suitable for determining bromate at 5 ppb in a matrix containing up to 50 ppm each of chloride, carbonate, and sulfate. For trace bromate analysis below 5 ppb in higher ionic strength matrices (where chloride levels exceed 50 ppm), the Dionex IonPac AS19 column is recommended. Alternatively, the Dionex IonPac AS27 column is recommended for higher ionic strength matrices preserved with EDA.<h5>Use with a High-Pressure IC system</h5>A high-pressure IC system such as the Thermo Scientific™ Dionex™ ICS-5000+, Dionex ICS-6000, or Dionex Integrion HPIC™ system is required to use this column under standard operating conditions.<h4>Specifications</h4><ul><li>Anion Exchange Capacity: 6 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 477 μeq</li><li>Column Chemistry: Hydroxide</li><li>For Use With (Application): Anion Exchange</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 5000 psi (345 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% HPLC Solvents</li><li>Stationary phase: Super Macroporous Resin</li><li>Format: Standard Bore</li><li>Packing Material: Ethylvinylbenzene/Divinylbenzene</li></ul>

Thermo Scientific Dionex IonPac AS32-Fast-4μm IC Columns

Resolve polythionates, persulfate, polysulfonated aromatics, and aromatic dyes and pigments with the Thermo Scientific Dionex IonPac AS32-Fast-4μm column.

Resolve polythionates, persulfate, polysulfonated aromatics, and aromatic dyes and pigments with the Thermo Scientific™ Dionex™ IonPac™ AS32-Fast-4μm column. The unique selectivity of the Dionex IonPac AS32-Fast-4μm column allows it to resolve trace amounts of perchlorate in matrices containing high levels of chloride and sulfate within ten minutes using simple, isocratic conditions. Compared to similar anion-exchange columns packed with 7-9μm resin particles, Dionex IonPac AS32-Fast-4μm columns produce more efficient peaks, resulting in more accurate integration and more reliable results.<h5>Superior Chromatographic Performance</h5><ul><li>High capacity allows injection of complex matrices without overloading the column while maintaining excellent peak shapes for lower concentration analytes.</li><li>Ultralow hydrophobicity and reduced 150mm column length allow for fast analysis of highly polarizable anions such as perchlorate and iodide with a simple, isocratic eluent.</li><li>Quickly separate disparate concentration ratios (1:1000) of perchlorate in high sulfate matrices using simple, isocratic conditions.</li><li>Separate polythionates such as dithionate, trithionate, and tetrathionate.</li><li>Separate color additives including FD&amp;C Yellow #5, FD&amp;C Yellow #6, FD&amp;C Blue #1, and FD&amp;C Red #40 using a hydroxide gradient.</li></ul><h5>Use with a High-Pressure IC system</h5>A high-pressure IC system, such as the <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/410">Thermo Scientific™ Dionex™ ICS-6000 HPIC system</a> or <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/408">Thermo Scientific™ Dionex™ Integrion™ HPIC system</a> is required to operate this column under standard conditions.<h4>Specifications</h4><ul><li>Anion Exchange Capacity: 126 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 126 μeq</li><li>Column Chemistry: Hydroxide</li><li>For Use With (Application): Anion Exchange</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 5000 psi (345 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% HPLC Solvents</li><li>Stationary phase: Super Macroporous Resin</li><li>Format: Standard Bore</li><li>Packing Material: Ethylvinylbenzene/Divinylbenzene</li></ul>

Thermo Scientific Dionex IonPac AS4A-SC IC Columns

For fast, isocratic separation of inorganic anions in environmental waters, the Thermo Scientific Dionex IonPac AS4A-SC column was the preferred column for many years. 

For fast, isocratic separation of inorganic anions in environmental waters, the Thermo Scientific™ Dionex™ IonPac™ AS4A-SC column was the preferred column for many years. It was first introduced in 1984 and is the specified column in U.S. EPA Method 300.0 (A). However, the advanced, high-capacity Dionex IonPac AS22 Carbonate Eluent Anion-Exchange column is recommended for fast analysis of inorganic anions in diverse matrices when using carbonate eluents.<h5>Fast Isocratic Separation of Inorganic Anions in Simple Matrices</h5><ul><li>Compliance monitoring of common anions in drinking water as specified in U.S. EPA Methods 300.0 (A)</li><li>Separation of common inorganic anions in 10 minutes in water, food and beverages, and other diverse sample matrices</li><li>Compatible with sodium tetraborate gradient to optimize difficult separations</li><li>Solvent compatibility for easy column cleanup after the analysis of samples with hydrophobic components</li></ul><h5>Multiple Formats Available for Application Flexibility</h5><ul><li>4×250mm, 2x250mm analytical columns</li><li>4×50mm, 2x50mm guard columns</li><li>Longer 250mm columns facilitate higher resolution separations of more complex sample matrices</li><li>Smaller i.d. columns provide higher mass sensitivity, eluent and reagent conservation and lower operating costs</li></ul>Note: Use with the Dionex IonPac AS4A Eluent Concentrate for simple, accurate eluent preparation.<h4>Specifications</h4><ul><li>Column Capacity: 20 μeq</li><li>Column Chemistry: Carbonate/Bicarbonate</li><li>Crosslinking: 0.5% DVB</li><li>For Use With (Application): Separation of Inorganic Anions, Anion Exchange</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 4000 psi (275 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% HPLC Solvents</li><li>Stationary phase: IonPac AS4A-SC</li><li>Packing Material: Ethylvinylbenzene/Divinylbenzene</li></ul>

Thermo Scientific Dionex IonPac AS9-SC IC Columns

Separate inorganic anions and oxyhalides in simple matrices using an isocratic carbonate/bicarbonate eluent with the Thermo Scientific™ Dionex™ IonPac™ AS9-SC Carbonate Eluent Anion-Exchange Column.

Separate inorganic anions and oxyhalides in simple matrices using an isocratic carbonate/bicarbonate eluent with the Thermo Scientific™ Dionex™ IonPac™ AS9-SC Carbonate Eluent Anion-Exchange Column. The Dionex IonPac AS9-SC column is specified in US EPA Method 300.0 (B), and meets or exceeds the performance requirements of this method. However, the advanced, high-capacity Dionex IonPac AS23 Carbonate Eluent Anion-Exchange column is recommended for determination of oxyhalides and inorganic anions, such as trace bromate, in ozonated drinking water.<h5>Fast Separation of Inorganic Anion and Oxyhalides in Simple Matrices</h5><ul><li>Compliance monitoring of common anions and oxyhalides in drinking water as specified in U.S. EPA Methods 300.0 (B)</li><li>Simple, isocratic separation of inorganic anions in less than 10 minutes in drinking water</li><li>Fast isocratic separation of inorganic anions and oxyhalides in ozonated drinking water matrices</li><li>Solvent compatibility permits easy column cleanup after the analysis of samples with hydrophobic components.</li></ul><h5>Formats Available for Application Flexibility</h5><ul><li>4x250mm analytical columns</li><li>4x50mm guard columns</li><li>Longer 250mm columns facilitate higher resolution separations of more complex sample matrices</li></ul><h4>Specifications</h4><ul><li>Column Capacity: 30 to 35 μeq</li><li>Column Chemistry: Carbonate/Bicarbonate</li><li>For Use With (Application): Separation of Oxyhalides and Inorganic Anions, Anion Exchange</li><li>Ion Exchange Group: Alkyl Quaternary Ammonium</li><li>Max. Pressure: 4000 psi (275 bar)</li><li>Solvent Compatibility: pH 2 to 11, 0 to 100% HPLC Solvents</li><li>Stationary phase: IonPac AS9-SC</li><li>Packing Material: Ethylvinylbenzene/Divinylbenzene</li></ul>

Thermo Scientific Dionex IonPac AS23-4μm IC Columns

Analyze trace bromate and other oxyhalides in drinking water, ground water, wastewater, and other diverse matrices using the Thermo Scientific™ Dionex™ IonPac™ AS23-4μm columns. 

Analyze trace bromate and other oxyhalides in drinking water, ground water, wastewater, and other diverse matrices using the Thermo Scientific™ Dionex™ IonPac™ AS23-4μm columns. The high capacity and selectivity of this column facilitates the determination of trace bromate at low-μg/L levels in the presence of high amounts of chloride, sulfate, and carbonate. Compared to <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2058">Dionex IonPac AS23 column</a>, the new Dionex IonPac AS23-4μm columns use smaller resin particles for more efficient separations resulting in more accurate peak integration and more reliable results.<h5>Designed Specifically for Trace Bromate Analysis in Drinking Water</h5><ul><li>Use the Dionex IonPac AS23-4μm for diverse matrices including drinking water, ground water, and waste water.</li><li>High capacity allows routine drinking water analysis without sample pretreatment or preconcentration.</li><li>Improved efficiencies and resolution compared to the <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2058">Dionex IonPac AS23 column</a>.</li><li>Easily transfer applications from the Dionex IonPac AS23 column to the AS23-4μm column due to the similar selectivity.</li><li>Compatible with organic solvents to enhance analyte solubility, modify column selectivity, and facilitate effective column clean-up.</li></ul><h5>Use With a High-Pressure IC System</h5>Higher resolution is achieved through the use of smaller resin particles, which produce a column backpressure over 3000psi at the standard flow rates. A high-pressure IC system, such as the Thermo Scientific™ Dionex™ ICS-5000+ HPIC™ or the Thermo Scientific™ Dionex™ Integrion™ HPIC™ system is required to operate this column under standard conditions and take advantage of elevated flow rates and faster run times.<h5>Multiple Formats Available</h5><ul><li>4x250mm and 2x250mm analytical columns</li><li>4x50mm and 2x50mm guard columns</li></ul>Note: Use the Dionex AS23 Eluent Concentrate for simple, accurate eluent preparation.<h4>Specifications</h4><ul><li>Anion Exchange Capacity: 320 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 320 μeq</li><li>Column Chemistry: Carbonate/Bicarbonate</li><li>For Use With (Application): Anion Exchange</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 5000 psi (345 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% HPLC Solvents</li><li>Stationary phase: IonPac AS23-4μm</li><li>Format: Standard Bore</li><li>Packing material: Polyvinylbenzyl Ammonium Polymer/Divinylbenzene</li></ul>

Thermo Scientific Dionex IonPac AS22 Fast IC Columns

Thermo Scientific™ Dionex™ IonPac™ AS22-Fast column combines the selectivity of the Dionex IonPac AS22 column with super-fast separation times. 

Designed specifically for compliance monitoring of inorganic anions in accordance with U.S. EPA Methods 300.0 (A), the Thermo Scientific™ Dionex™ IonPac™ AS22-Fast column combines the selectivity of the <a target="_blank" rel="noopener noreferrer" href="https://lcms.labrulez.com/products/2057">Dionex IonPac AS22 column</a> with super-fast separation times. With the Dionex IonPac AS22-Fast column, you can quickly and simply separate common inorganic anions from a variety of sample matrices including drinking water, wastewater, process streams, and scrubber solutions.<h5>Super Fast Analysis of Inorganic Anions and Low Molecular Weight Organic Acids in Diverse Matrices</h5><ul><li>Compliance monitoring of common anions in drinking water as specified in U.S. EPA Method 300.0 (A)</li><li>Super-fast isocratic separation of common inorganic anions in less than 5 min in diverse matrices such as drinking water, surface water, groundwater, and wastewater</li><li>Sufficient capacity to maintain resolution even in a short column format, which helps laboratories achieve higher productivity and increased throughput</li><li>Excellent resolution of the carbonate peak away from the common inorganic anions</li><li>Faster alternative, using carbonate/bicarbonate eluents, for Dionex IonPac AS4A-SC, AS12A, AS14, AS14A and AS22 inorganic anion applications.</li><li>Solvent compatibility permits easy column cleanup after the analysis of samples with hydrophobic components.</li></ul><h5>Multiple Formats Available for Application Flexibility</h5><ul><li>4x150mm, 2x150mm analytical columns</li><li>4x30mm, 2x30mm guard columns</li><li>Shorter 150mm columns produce faster runs of relatively clean matrices</li><li>Smaller i.d. columns provide higher mass sensitivity, eluent and reagent conservation and lower operating costs</li></ul>Note: For simple, accurate eluent preparation, use the Dionex IonPac AS22 Eluent Concentrate.<h4>Specifications</h4><ul><li>Anion Exchange Capacity: 126 μeq</li><li>Crosslinking: 55% DVB</li><li>Column Capacity: 126 μeq</li><li>Column Chemistry: Carbonate/Bicarbonate</li><li>For Use With (Application): Anion Exchange</li><li>Ion Exchange Group: Alkanol Quaternary Ammonium Ion</li><li>Max. Pressure: 3000 psi (207 bar)</li><li>Solvent Compatibility: pH 0 to 14, 0 to 100% HPLC Solvents</li><li>Stationary phase: IonPac AS22-Fast</li><li>Format: Standard Bore</li><li>Packing Material: Polymeric</li></ul>

Products from category HPLC columns focused on Ion chromatography - page 3

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