Ion chromatography (IC) is a widely used analytical technique for the separation and determination of anionic or cationic analytes in various sample matrices. Today, it is performed in several separation and detection modes. But that wasn’t always the case, especially when it debuted on the analytical laboratory marketplace in 1975—exactly 50 years ago.
Even as we celebrate IC’s 50th anniversary, the fundamentals of the technique have not changed. The core principle of IC is still conductivity detection. Although modern detectors are highly sensitive and include features like temperature compensation, the fundamental setup remains a straightforward anode-cathode system that measures changes in the conductivity of ions.
Of course, there are many areas in which IC has advanced over the last 50 years, especially considering how overall technology has improved in that time. To take a deeper look at the past, present and future of IC, Labcompare spoke with Andriy Savka, HPLC Product Specialist at Shimadzu Scientific Instruments, and renowned IC expert Jay Gandhi, Vertical Market Manager at Metrohm USA.
Be sure to check back next month for part 2 of this interview as we continue to celebrate 50 years of IC!
Labcompare: What overall improvements have been made to IC over the years?
Gandhi: Key advancements include the development of sophisticated liquid handling systems for enhanced automation and precision, the introduction of small-bore columns improving separation efficiency and reducing eluent consumption, the transition to digital signal processing for greater accuracy and data integrity, and a significant increase in analytical sensitivity, enabling the detection of analytes at much lower concentrations.
Savka: The key focus of improvement in Ion Chromatography has remained consistent over the years: enhancing sensitivity and resolution, while also improving ruggedness and versatility. Notable advancements include the development of various suppression techniques, a growing emphasis on eco-friendly methods, and efforts to reduce the overall footprint. In addition, there is an increasing focus on advanced software and automation to streamline workflows and enhance data processing.
Labcompare: In your opinion, what is the single biggest advancement to IC technology since its introduction?
Gandhi: In my opinion, the single most impactful breakthrough for IC technology has been the substantial enhancement of detection limits. This progress is largely attributable to the adoption of digital signal processing and detector improvements, which allow for more precise measurement and quantification of analytes at previously undetectable trace and ultra-trace levels.
Savka: Suppression is considered the most significant advancement in Ion Chromatography, as it has improved sensitivity by up to three orders of magnitude, enabling detection at much lower concentration levels. With the introduction of suppressed IC, many analytical methods became feasible within this technique—methods that previously required alternative instrumentation due to sensitivity limitations.
Labcompare: What can IC do now that it couldn't do in the 1970s?
Gandhi: The integration of sophisticated automation for sample preparation (such as automated dilution or matrix elimination) and advanced liquid handling routines allows for higher throughput, improved reproducibility, and complex analytical sequences (like automated calibration or pre-concentration) that were previously impractical or impossible to perform manually with precision.
Savka: Thanks to advancements over the years in suppression techniques, modern column technology, and improvements in liquid chromatography (LC) modules, Ion Chromatography (IC) can now detect a wide range of ions with high efficiency. Compared to the manually operated analog systems of the past, today’s IC instruments offer a high degree of automation and software integration, significantly enhancing testing accuracy and productivity.
Labcompare: Application-wise, is there an area that IC works with today that the technology was not suited for decades ago?
Gandhi: A prime example of an application area where IC now thrives is its use in hyphenated techniques. Specifically, the coupling of IC with Mass Spectrometry (IC-MS) has unlocked powerful capabilities for elemental and molecular speciation – determining not just the presence and quantity of an analyte, but its specific chemical form (e.g., oxidation state of a metal), which is crucial in fields like environmental toxicology, clinical analysis, and food science.
Labcompare: How has customer demand for IC grown in 50 years?
Gandhi: Customer demand for Ion Chromatography has expanded considerably over the last five decades. This growth is intrinsically linked to the technology's continuous improvements in sensitivity, selectivity, and automation. As IC systems became capable of delivering more reliable results for lower concentrations and distinguishing between closely related analytes in complex samples, demand surged for more sophisticated applications. This fueled significant market growth, particularly within regulated sectors such as food safety, pharmaceutical quality control, and advanced environmental monitoring (e.g., drinking water and ultrapure water analysis).
Labcompare: How have hyphenated methods changed IC technology?
Gandhi: The coupling with Mass Spectrometry (IC-MS) represents a paradigm shift, vastly improving both sensitivity and selectivity, enabling definitive identification and quantification of trace analytes even in challenging matrices. Concurrently, the hyphenation of automated sample preparation modules (like inline filtration, dilution, or matrix elimination) has broadened the analytical scope, especially within environmental monitoring samples like air, water or soil.
Labcompare: What are some best practices for conducting IC analysis today?
Gandhi:
- Prioritize Eluent and Water Purity: Employing high-purity, reagent-grade water (e.g., ASTM Type I) and freshly prepared, filtered eluents is non-negotiable for reliable IC analysis. This is especially critical when targeting trace or ultra-trace analyte concentrations to minimize baseline noise, prevent contamination, and ensure accurate quantification.
- Leverage Automation for Consistency and Efficiency: Utilize the capabilities of modern autosamplers and liquid handling systems to implement automated workflows. This includes routines like multi-level calibrations, standard additions for complex matrices, and intelligent, condition-based sample dilutions.
- Employ Hyphenation (IC-MS) for Complex Challenges: When faced with intricate matrices, the need for analyte confirmation, or the requirement for extremely high sensitivity and selectivity (e.g., speciation studies, analysis of emerging contaminants like PFAS, perchlorate, or trace metal species in food and environmental samples), capitalize on the definitive power of hyphenated
Savka: Some good practices for Ion Chromatography include using IC-grade or better deionized (DI) water for testing, performing regular preventive maintenance (PM) on system consumables, and properly filtering your samples before injection. These steps help ensure accurate results, extend the life of your equipment, and minimize the risk of contamination or system downtime.
About the interviewees
Metrohm's Dr. Jay Gandhi brings 35+ years of proficiency with virtually all analytical instrumentation and the techniques of Environmental, Petrochemical and Pharmaceutical testing and research. He has shepherd several ASTM and USEPA methods and has received several prestigious awards from the likes of the DuPont company, NASA, Varian Inc. and ASTM International.
Andriy Savka is the HPLC Product Specialist at Shimadzu Scientific Instruments. He specializes in quantitative and qualitative chemical analysis testing within cGLP regulated environments. He is adept at diagnosing and resolving intricate repair issues, showcasing a successful track record in maintaining and troubleshooting diverse chemistry lab instruments.