John Chasse

Articles by John Chasse

Researchers have optimized a headspace sorptive extraction (HSSE) method coupled with gas chromatography-mass spectrometry (GC-MS) to analyze human scent traces left on clothing. By extracting volatile and semi-volatile organic compounds and applying supervised machine learning algorithms, such as support vector machines (SVM) and partial least squares-discriminant analysis (PLS-DA), to the GC-MS data, the team achieved 100% accuracy in gender discrimination. This combination of optimized extraction, GC-MS analysis, and machine learning provides a rapid and automated forensic screening technique to help narrow down suspect or victim profiles based on trace evidence.

Researchers successfully employed high-performance liquid chromatography with fluorescence detection (HPLC-FLD) to analyze atmospheric polycyclic aromatic hydrocarbons (PAHs) across Quebec using Pleurozium schreberi moss. The chromatographic analysis targeted 10 PAHs to establish a rigorous spatial baseline of pollution and 15 PAHs to measure the environmental impact of the severe 2023 Canadian wildfires. The HPLC-FLD data revealed that while the wildfires did not increase total PAH concentrations, they caused distinct compositional shifts, proving the effectiveness of this analytical method in detecting regional pollution gradients and temporal source changes.

A worldwide study involving 12 research groups has confirmed that capillary zone electrophoresis combined with mass spectrometry (CZE-MS) is a highly reproducible and sensitivealternative to traditional methods for analyzing proteoforms, offering a way to separate these critical protein variations based on their charge-to-size ratio. LCGC International spoke to Kevin Jooß of the Vrije Universiteit Amsterdam, one of the authors of a paper outlining the study, about this work.

Headspace solid-phase microextraction-gas chromatography–mass spectrometry (HS-SPME/GC-MS) and high-performance liquid chromatography with diode-array detection (HPLC-DAD) were used to evaluate 45 Brazilian artisanal chocolates, identifying 72 volatile compounds and quantifying methylxanthines. Results demonstrated that theobromine and caffeine concentrations strongly correlate with declared cocoa content, proving these chromatographic methods provide a reliable workflow for quality control, traceability, and fraud prevention in chocolate manufacturing.

Headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry HS-SPME-GC-MS was used by researchers to analyze volatile organic compounds (VOCs) during goat cheese ripening over 150 days. They identified 68 VOCs and found that 2-butanone and 2-butanol serve as potential markers for the final maturation stage, offering a simple, low-cost method for early monitoring of cheese ripening.

Researchers utilized gas chromatography (GC) to evaluate and compare the fatty acid compositions of plant-based meat substitutes and traditional ground beef available on the market. Following homogenization and lipid extraction, the GC data revealed distinct fatty acid profiles between the two groups. The analysis demonstrated that most plant-based alternatives exhibited higher polyunsaturated fatty acid levels and more favorable nutritional indices—such as the unsaturation and hypocholesterolemic indices—compared to beef, though the researchers noted that the specific health implications rely heavily on the diverse types of oils used in each plant-based product.

Gas chromatography-mass spectrometry (GC-MS) and orthogonal partial least squares (OPLS) regression to analyze both volatile and non-volatile compounds in five strawberry cultivars. The study successfully correlated specific compounds with sensory profiles like sweetness and flavor, offering valuable insights to improve predictive models and guide future strawberry breeding programs.

Researchers investigated the effects of electron beam irradiation on cold fresh rainbow trout using GC×GC-MS and lipidomics. The chromatographic analysis revealed that while low doses preserve quality, doses of 3 kGy or higher accelerate lipid oxidation, significantly increasing volatile flavor compounds and causing unwanted irradiation odors that lower sensory acceptability.

Gas chromatography coupled with quadrupole mass spectrometry (GC-qMS) and high-performance liquid chromatography equipped with diode-array and refractive index detectors (HPLC-DAD/RI) to analyze the chemical and aromatic profiles of kombucha fermented with pineapple, fennel, and carrot by-products. The chromatographic data revealed how specific microbial communities interact with these plant residues to produce unique volatile organic compounds, demonstrating a sustainable approach for value-added beverage production.

High-performance liquid chromatography (HPLC) was used in a study measuring and monitoring vitamin C concentrations in the breast milk of postpartum mothers in Malaysia. The HPLC data revealed that average vitamin C levels were lower than those commonly reported in other populations, particularly during the initial weeks following childbirth. By accurately tracking these fluctuations using HPLC, the study established a significant correlation between early vitamin C levels and maternal fruit consumption, highlighting the critical need for targeted nutritional education to ensure adequate antioxidant intake during the postpartum period.

Researchers used headspace solid-phase microextraction–gas chromatography–mass spectrometry (HS-SPME-GC-MS) to profile volatile compounds in chicken soup prepared using low-voltage electrostatic field (LVEF)-assisted stewing. The treatment increased VOC diversity and abundance, enabling a 15% sodium reduction while enhancing saltiness, umami perception, protein content, and overall flavor quality without compromising stability.

Using thermal desorption–gas chromatography–mass spectrometry (TD-GC-MS), researchers quantified volatile organic compound emissions from nine tactile toys and observed scaling of VOC release with product mass and surface area. Hazardous solvent residues such as dimethylformamide and methylene chloride produced an initial high-concentration emission burst, underscoring the need for standardized emission testing.

Liquid chromatography-mass spectrometry (LC–MS) was used in combination with 16S rDNA sequencing to analyze the upper respiratory tract microbiomes and metabolomes of children with asthma. The LC–MS analysis uncovered significant metabolic variations between chronic persistent and acute exacerbation asthma groups, identifying L-carnitine as a highly accurate differential metabolite and a promising biomarker for evaluating pediatric asthma.

Researchers applied ultra-performance liquid chromatography coupled to electrospray ionization quadrupole-time-of-flight mass spectrometry (LC–ESI-QTOF–MS) and gas chromatography-mass spectrometry (GC–MS) to comprehensively profile bioactive peptides and short-chain fatty acids (SCFAs) in mixed-species probiotic yogurt. These chromatographic and mass spectrometric analyses demonstrated how specific Lacticaseibacillus and Bifidobacterium strains enhance the production of therapeutic metabolites, successfully identifying novel short peptides and providing actionable insights for developing functional, health-oriented dairy products.

Size-exclusion chromatography (SEC) was used to purify extracellular vesicles (EVs) from the plasma of chronic myeloid leukemia (CML) patients to evaluate treatment responses and mutation statuses. This study demonstrates that precisely isolating EVs using chromatography allows for deep proteomic analysis, which can provide valuable insights into a patient's clinical status and reveal potential biomarkers for monitoring CML treatment response, remission, and drug resistance.

By utilizing gas chromatography-olfactometry-mass spectrometry (GC-O-MS) alongside stirred barrel sorption extraction and pyrolysis, researchers were able to systematically track how aromatic compounds in cigar tobacco leaves transform into mainstream smoke. Pinpointing these complex chemical transitions allowed this GC-O-MS approach to provide a scientific foundation for precisely evaluating cigar quality, optimizing formulations, and understanding the sensory experiences that drive consumer preference.

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) to measure plasma concentrations of the oxysterols 24 S-OHC and 27-OHC was used to evaluate their potential as biomarkers for early-onset schizophrenia (EOS). These chromatography-derived insights suggest that sexually dimorphic cholesterol metabolism may play a role in the differing clinical expressions of EOS, offering new avenues for understanding underlying disease mechanisms.

Researchers developed a green, supramolecular solvent-based microextraction approach using naturally occurring components (decyl glucoside and linalool) to preconcentrate toxic benzimidazole fungicides (thiabendazole and carbendazim) from vegetable samples. Following the extraction, high-performance liquid chromatography with fluorescence detection (HPLC-FLD) was utilized to precisely determine the fungicide levels. This environmentally friendly chromatography method achieved high extraction recoveries (over 98%) and reliable precision in real vegetable matrices (such as potato, beetroot, and ginger), demonstrating its robust potential for monitoring hazardous agricultural residues and ensuring food safety.

UHPSFC/MS Lipidomic Profiling for Early Detection of Pancreatic Cancer

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Ultrahigh-performance supercritical fluid chromatography-mass spectrometry (UHPSFC/MS) was used to perform lipidomic profiling of plasma and serum samples to develop a noninvasive, blood-based diagnostic tool for pancreatic ductal adenocarcinoma (PDAC). The findings suggest that UHPSFC/MS lipidomic profiling holds significant promise as a highly sensitive and specific screening method for early-stage pancreatic cancer, potentially outperforming current diagnostic standards.

A novel workflow combining comprehensive two-dimensional gas chromatography (GC×GC) with computer vision (CV) was developed to analyze the complex volatile profiles of coffee. By generating composite class images and using targeted extraction alongside multivariate analysis, the approach successfully overcame analytical challenges to accurately identify key characteristic compounds. This reproducible, data-driven method offers a reliable strategy for distinguishing coffee origins and assessing quality based on its intricate chemical makeup.

A pilot study utilizing comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GCxGC-TOF MS) to analyze volatile compounds in the breath of patients successfully identified specific breath markers that can effectively differentiate the life-threatening infectious disease melioidosis from other febrile illnesses with high sensitivity and specificity.

Researchers used LC-MS/MS to analyze 52 sake samples from Japan for neonicotinoids and other insecticides. 88% contained detectable insecticides, with dinotefuran being the most common. Contamination levels were comparable to Asian red wines but exceeded EU red wines. While individual risks appear low, the combined effects of alcohol and insecticides raise concerns.

Ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC–QTOF-MS) was used for the analysis of serum and urine metabolites in patients with cirrhosis. By identifying dysregulated pathways—including tryptophan and glycerophospholipid metabolism—researchers established a dual-biofluid diagnostic strategy. This metabolomics approach offers a non-invasive method for identifying biomarkers and potential therapeutic targets for liver cirrhosis detection.

Osaka University researchers developed a non-destructive model to predict banana ripeness by analyzing emitted volatile organic compounds (VOCs). Using gas chromatography-mass spectrometry (GC-MS) and orthogonal partial least squares (OPLS) regression, they accurately linked VOC composition to color and sugar content. This metabolomics-based approach aims to replace destructive testing, offering a practical tool for improving banana supply chain management.

Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to quantify creatine, creatinine, and guanidinoacetic acid in saliva and serum samples from young adults before and after exercise. While salivary creatine and creatinine levels increased significantly post-exercise, serum creatine remained stable, highlighting distinct metabolite dynamics between these two biological fluids during physical exertion.

A recent study employed high-throughput liquid chromatography-mass spectrometry (LC-MS) to perform comprehensive metabolic profiling on plasma samples from nearly 4,000 women. By leveraging the separation power of chromatography and the sensitivity of mass spectrometry, researchers identified specific metabolic perturbations, such as steroid esters and triglycerides, linked to the risk of hearing loss. These findings demonstrate how automated analytical platforms can uncover novel biomarkers and potential therapeutic targets for complex sensory disorders.