Best of the Week: Pesticide Residue Analysis, 50 Years of Ion Chromatography

This week, LCGC International published a variety of articles on hot topics in separation science. From an interview about the evolution of ion chromatography to a discussion about using ultrahigh-pressure liquid chromatography (UHPLC) coupled with tandem mass spectrometry (MS) to analyze 26 per- and polyfluoroalkyl substances (PFAS), we’ve highlighted some of the most popular articles that were published this week.

Pesticide Residue Analysis in Food: Advances, Challenges, and Case Studies

Pesticide residue analysis is evolving to support exposomics, a holistic approach to understanding total chemical exposure from food and the environment. Recent research highlights advances in high-throughput mass spectrometry, liquid chromatography (LC)– and gas chromatography (GC)–based “mega-methods,” and ion mobility–high-resolution mass spectrometry (HRMS) coupling to expand compound coverage and resolve interferences (1). Studies demonstrate practical applications, including multiresidue screening in date fruits, lufenuron risk assessment in cabbage, and GC workflows for animal-derived foods. Common themes include balancing multi-residue breadth with analytical rigor, addressing matrix complexity, and linking results to risk assessment (1). The field is progressing toward standardized, exposome-informed methods that strengthen food safety and public health insights (1).

Fifty Years Of Ion Chromatography (IC): An Interview with IC Pioneer Joachim Weiss (Part 2)

In this interview, Joachim Weiss addresses misconceptions about ion chromatography (IC), emphasizing that modern systems with suppressors make hydroxide or methanesulfonic acid eluents fully compatible with MS detection. He highlights IC’s superiority for analyzing ionic pesticides and regulatory compliance testing, noting its unmatched sensitivity, selectivity, and versatility across environmental and agricultural applications (2). Weiss discusses advances such as high-pressure IC, new resin materials, and automation features like eWorkflows and radio frequency identification (RFID) tracking that improve speed and ease of use (2). He encourages young chromatographers to specialize in IC, underscoring its growing importance and enduring innovation after 50 years of development.

Expanding Human Hair Biomonitoring for PFAS: Broadening Analyte Coverage to Emerging Compounds

In this interview, Miriam Haußecker of the Eberhard Karls University of Tübingen discusses her team’s use of ultrahigh-pressure liquid chromatography (UHPLC) coupled with tandem MS to analyze 26 PFAS compounds, including emerging contaminants like NTf₂, in human hair. The study highlights hair’s potential as a non-invasive biomonitoring matrix but notes challenges with complex matrices and external contamination (3). Careful pre-washing, solid-phase extraction, and isotope-labeled standards helped minimize matrix effects. Chromatography enabled semi-quantitative distinction of PFAS isomers, essential for source tracking (3). Haußecker emphasizes the need for standardized protocols, non-targeted screening, and advanced chromatographic techniques like 2D-LC and HRMS to improve PFAS detection and comparability across studies (3).

Impact of Blood Collection Materials on LC-MS/MS Measurement of Vitamin D

A new study in The Journal of Applied Laboratory Medicine examined how blood collection tube materials affect serum 25-hydroxyvitamin D [25(OH)D] measurements by liquid chromatography tandem mass spectrometry (LC–MS/MS). Despite LC-MS/MS being the gold standard for drug and hormone analysis, its implementation in clinical labs remains challenging because of preanalytical variability (4). Researchers compared 20 tube types from different manufacturers and found significant measurement discrepancies, particularly interference caused by certain separator gels that distorted chromatograms (4). These results emphasize the need to evaluate tube materials before clinical use and to adopt international LC–MS/MS standards to ensure accuracy and reliability in laboratory measurements.

Tackling the Heat: Overcoming Matrix Challenges in Pesticide Residue Analysis of Chili Powder Using LC–MS/MS

In this interview, Raviraj Chandrakant Shinde discusses developing a high-throughput LC–MS/MS method for quantifying 135 pesticides in chili powder, a matrix complicated by pigments, oils, and capsinoids. His team optimized acetonitrile-based extraction and dispersive solid-phase extraction (d-SPE) cleanup using PSA, C18, and GCB sorbents to minimize matrix effects and ion suppression while preserving recoveries (5). The method demonstrated strong reproducibility across chili powders of varying origins, achieving RSDs below 15% (5). Shinde emphasizes matrix-matched calibration, isotopically labeled standards, and rigorous quality control for routine monitoring (5). Future work aims to expand pesticide coverage and simplify sample preparation using automated or reduced-prep workflows for complex spice matrices.

References

1. Jones, K. Pesticide Residue Analysis in Food: Advances, Challenges, and Case Studies. LCGC International. Available at: https://www.chromatographyonline.com/view/pesticide-residue-analysis-in-food-advances-challenges-and-case-studies (accessed 2025-10-16).
2. Matheson, A. Fifty Years Of Ion Chromatography (IC): An Interview with IC Pioneer Joachim Weiss (Part 2). LCGC International. Available at: https://www.chromatographyonline.com/view/fifty-years-of-ion-chromatography-ic-an-interview-with-ic-pioneer-joachim-weiss-part-2- (accessed 2025-10-16).
3. Chasse, J. Expanding Human Hair Biomonitoring for PFAS: Broadening Analyte Coverage to Emerging Compounds. LCGC International. Available at: https://www.chromatographyonline.com/view/expanding-human-hair-biomonitoring-for-pfas-broadening-analyte-coverage-to-emerging-compounds (accessed 2025-10-16).
4. Chasse, J. Impact of Blood Collection Materials on LC-MS/MS Measurement of Vitamin D. LCGC International. Available at: https://www.chromatographyonline.com/view/impact-of-blood-collection-materials-on-lc-ms-ms-measurement-of-vitamin-d (accessed 2025-10-16).
5. Jones, K. Tackling the Heat: Overcoming Matrix Challenges in Pesticide Residue Analysis of Chili Powder Using LC–MS/MS. LCGC International. Available at: https://www.chromatographyonline.com/view/tackling-the-heat-overcoming-matrix-challenges-in-pesticide-residue-analysis-of-chili-powder-using-lc-ms-ms (accessed 2025-10-16).