Steve Smith

This study demonstrates that GC–TOF-MS can be a useful approach to generate comprehensive fragrance profiles of essential oils. Peak deconvolution enables discrimination between closely eluted compounds, and soft electron ionization, assisted by comparison of ion ratios, makes it possible to discriminate between isomeric monoterpenes with very similar mass spectra at conventional 70-eV ionization energies.

The inherent sensitivity and selectivity of time-of-flight mass spectrometry (TOF-MS) can be augmented by soft electron ionization (EI) to provide ultratrace-level quantitation of organotins in complex environmental extracts. These organotin species are a focus of current concern as environmental contaminants, but analysis using conventional 70 eV ionization energies is made difficult by their propensity to undergo extensive fragmentation. The use of soft EI helps to solve this problem by producing simplified spectra with enhanced diagnostic ions.

Solid-phase microextraction (SPME) coupled with comprehensive two-dimensional gas chromatography and time-of-flight mass spectrometry (GC×GC–TOF-MS) can be used to detect trace-level fungicides and compounds responsible for undesirable attributes known as “organoleptic faults” in wine. Of particular interest is the analysis of trace-level fungicides, which are difficult to detect using conventional quadrupole GC–MS techniques without resorting to selected ion monitoring mode. 

GC?GC–TOF-MS is used in forensic analysis for the analysis of tear gas lachrymators. In this article the analysis of a lachrymator standard is shown first, followed by the detection of capsaicin and dihydrocapsaicin at trace levels in a complex extract from contaminated clothing.

Microwave-accelerated extraction (MAE) is described and evaluated. The latest enhancements to this technology are discussed from a hardware and applications perspective.

Microwave-accelerated extraction (MAE) is described and evaluated. The latest enhancements to this technology are discussed from a hardware and applications perspective.

Microwave accelerated extraction (MAE) was evaluated by the authors of this review in 1999 (1). Since this time, the United States Environmental Protection Agency (USEPA) has promoted the use of SW-846 Method 3546 using MAE for the extraction of organic compounds from solid matrices.

A carefully chosen analytical technique can enhance the inherent advantages of passive sampling of watercourses over more traditional "grab" or "spot" sampling.