John Chasse

Articles by John Chasse

Aiming to determine the presence of heroin, fentanyl, amphetamine-type stimulants (ATS), xylazine, and other substances in Tijuana and Mexicali, Baja California, researchers randomly selected 300 drug residues from confiscated syringe plungers. After analyzing them with gas chromatography–mass spectrometry (GC–MS) and BTNX test strips for ATS and fentanyl and its analogs, the test strips showed a high positive predictive value of 81% when compared with GC–MS.

Emerging blood microsampling technologies offer a promising alternative by enabling minimally invasive, user-friendly collection, facilitating repeated sampling and broader population recruitment. A recent study conducted at Stockholm University critically reviewed commercially available microsamplers, their use in multiomics research, and experimentally evaluated their chemical backgrounds. LCGC International spoke to Solveig Thiele, lead author of the resulting paper, about this work.

Egyptian scorpions of the Androctonus genus produce neurotoxic venom that result in life-threatening stings. However, the composition and enzymatic activities of their venoms remain poorly understood. Researchers used electrophoresis to analyze the protein components of venom collected from three Androctonus species, with high-performance liquid chromatography (HPLC) and mass spectrometry (MS).

As a response to the growing interest in identifying novel, non-invasive biomarkers reflecting endogenous inflammatory processes in asthma, researchers evaluated the presence of volatile organic compounds (VOCs) in exhaled breath from patients with clinically controlled asthma to assess how tobacco exposure influences their expression. Breath samples were analyzed using gas chromatography-mass spectrometry (GC-MS).

Researchers optimized two-dimensional liquid chromatography (2D-LC) using a Design of Experiments-guided optimization approach to overcome breakthrough effects, enabling high-resolution oligonucleotide impurity profiling beyond conventional 1D-LC. LCGC International spoke to Megane Aebischer of the Institute of Pharmaceutical Sciences of Western Switzerland, lead author of the paper that resulted from this work.

Researchers developed a technique optimizing the extraction process of six cannabinoids in cannabis oil and marijuana samples, as well as an analytical validation of a quantitative and qualitative method for seven cannabinoids, using ultrahigh-performance liquid chromatography coupled with low-resolution mass spectrometry (UHPLC-LTQ-MS).

Responding to a lack of sensitive analytical methods for detecting associated medications in complex wastewater matrices, researchers at the University of Louisville developed and validated a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method using multiple reaction monitoring for 10 common respiratory pharmaceuticals.

A research team comprised of members of the University of Liège and the College of William & Mary developed a robust analytical workflow to profile volatile organic compounds (VOCs) emitted during accelerated thermal aging of smokeless powders formulated with those green stabilizers. Headspace solid-phase microextraction coupled with comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (HS-SPME–GC×GC–TOFMS) provided high peak capacity and sensitive VOC detection. LCGC International spoke to Pierre-Hugues Stefanuto of the University of Liège about this workflow and its potential implications for future research.

Researchers investigating how beer and the hepatopancreas influence the flavor of red swamp crayfish assessed the effects of cooking with or without the hepatopancreas in beer or water on crayfish quality using sensory analysis, electronic nose technology, and gas chromatography–ion mobility spectrometry (GC-IMS).

Researchers aiming to determine the optimal harvest time for maximum essential oil and linalool yields from basil hydro distilled the dried leaves of gathered plant samples for extraction of essential oil and subjected the resulting produce to gas chromatography-mass spectrometry (GC-MS) analysis to determine the variance in chemical compounds composition.

Silica stationary phases are traditionally prepared through silanization, where silanol groups on the silica surface react with organosilanes to create chemically bonded layers, typically with hydrocarbon chains such as C18 or C8 for reversed-phase separations. A research team from the Department of Chemistry at the University at Buffalo introduced an alternative surface modification method that avoids silanization, using diazonium chemistry instead. LCGC International spoke to Luis A. Colón, corresponding author of the paper that resulted from the team's research, about the method.

This edition of LCGC International’s “Equipment Roundup” spotlights Shimadzu’s i-Series LC-2070/LC-2080 Integrated High-Performance Liquid Chromatographs, and recent software upgrades to their ACD/Labs Spectra and Percepta platforms.