Scientists Determine Cause of Odors in Car AC Units using GC Methods
Scientists from Kangwon National University in South Korea undertook a comprehensive study to identify the types of compounds in vehicle AC unit emissions, using gas chromatography with four types of detection: olfactometry, flame ionisation detection (FID), mass spectrometry (MS) and atomic emission detection (AED). It was conducted on a lab-scale model unit that contained a rogue AC evaporator from a vehicle that was associated with unpleasant odours and had only 4000 km on the clock.
Scientists from Kangwon National University in South Korea undertook a comprehensive study to identify the types of compounds in vehicle AC unit emissions, using GC with four types of detection: olfactometry, flame ionisation detection (FID), mass spectrometry (MS) and atomic emission detection (AED). It was conducted on a lab-scale model unit that contained a rogue AC evaporator from a vehicle that was associated with unpleasant odours and had only 4000 km on the clock. Twelve separate odor components were isolated by the sniffers. Four of these were too weak to be characterised but the remaining eight included notes such as plastic, sour, burnt, fragrant and greasy/oil-like. The various analyses revealed that there were no sulphur- or nitrogen-containing compounds but nine contained oxygen. Most were identified by GC-MS library searching as alcohols, acids, aldehydes, ketones, and ethers. The team were prevented from reporting the individual identities of the odorous compounds by the company funding the research, which classified that information as confidential.
Detangling the Complex Web of GC×GC Method Development to Support New Users
September 12th 2024The introduction of comprehensive two-dimensional gas chromatography (GC×GC) to the sample screening toolbox has substantially increased the ability to comprehensively characterize complex mixtures. However, for many gas chromatography (GC) users, the thought of having to learn to develop methods on a new technology is daunting. Developing a basic GC×GC method for most (nonspecialized) applications can be accomplished in minimal time and effort given parameter suggestions and ranges to target analytes in a sample of interest. In this article, the authors work describe a simple workflow to develop a GC×GC method for a specific sample upon initial use, with the aim of decreasing the time to accomplish functional workflows for new users.
The Reality Behind Column Insertion Distance
September 10th 2024Column insertion distance is critical to good chromatography. What happens if the column is installed too low in the injection port? Is insertion distance more important when performing split injection or splitless injection? Does the position of the column in the injection port impact reproducibility?
