What’s New in Chromatography?

Take a deep breath. The FDA has issued an emergency use authorization for InspectIR’s COVID-19 Breathalyzer – the first breath-based diagnostic that uses GC-MS for analysis of volatile organic compounds produced by the body when it’s fighting off COVID-19. The decision cited studies showing the breathalyzer was 91.2 percent sensitive (the percent of positive samples the test correctly identified) and 99.3 percent specific (the percent of negative samples the test correctly identified), with a false-negative rate of less than one percent, according to the agency.

Long COVID’s hidden impact? Researchers from India have discovered that COVID-19 alters levels of fertility-related proteins in men, via LC-MS/MS proteomic analysis. The pilot study – involving 10 healthy men and 17 men who had recently recovered from COVID-19 – suggests that even mild or moderate illness could reduce sperm count and motility, as well as reduce the number of normally shaped sperm. When the researchers analyzed semen proteins, they found 27 proteins at higher levels and 21 proteins at lower levels – many of which are involved in reproductive function – in COVID-19-recovered men compared with the control group.

Do you love that “new car” smell? In China, manufacturers generally try to eliminate the recognizable odor; in the US, you can buy fragrances that emulate it. But what makes up the aroma? For the first time, the odorants from vehicle interiors were investigated using gas chromatography-olfactometry combined with descriptive sensory analysis. Using this approach, 41 potent odorants were detected, and 39 odorants were successfully identified by 2D GC-MS. The most dominant odorants included esters, saturated and unsaturated aldehydes, unsaturated ketones, rose ketones, phenolic and benzene derivatives, and pyrazines. 

The e-connoisseur. Two-dimensional gas chromatography–time-of-flight mass spectrometry-based electronic nose - thankfully called NOS.E – can distinguish between different brands, origins, and styles of whisky by “sniffing” the liquor. In the study, the e-nose reached 100 percent accuracy for detecting the region, 96.15 percent accuracy for brand name and 92.31 percent accuracy for style. According to the University of Technology Sydney press release, the e-nose technology has also been used to detect illegal animal parts, such as black rhino horns, sold on the black market. 

Cranberry crowned king. The nutraceutical market has grown significantly in recent years, with many pharma companies manufacturing products based on different plant leaves, flowers and fruits thanks to their medicinal (mostly antioxidant) properties.  Flavonoids represent 60 percent of nutraceutical polyphenolic compounds, and so a team of researchers from the University of Barcelona have used a new method to determine polyphenols in nutraceutical samples, based on solid-liquid extraction and liquid chromatography. The super short version: cranberry samples were the richest in flavanols and artichoke samples were at the bottom of the list.

Also in the News… 
 

Henan Normal University, China, team develops a modified method for determining fatty acids in small fish samples – including lipid extraction, column selection, chromatographic condition optimization, and data analysis. Link

Sticking with fish… The German Federal Institute for Risk Assessment (BfR) breaks new ground in detecting ciguatoxin in fish, even when the fish’s origin is unknown, using LC-MS. Link 

It isn’t possible to consistently predict isocratic retention factors – helpful for simulating liquid chromatography methods – for small molecules with accuracies better than 10 percent, researchers find. Link