James Kapron is a strategic marketing specialist at Thermo Electron Corporation, Scientific Instruments Division, based in Ottawa, Ontario, Canada.
FAIMS Removes Chemical Background and Interference from the Analysis of Linoleic Acid in Cancer Cell Extracts
Assay sensitivity is the lowest concentration at which a targeted analyte can be measured and is often limited by chemical background or co-eluting interferences. FAIMS in combination with liquid chromatography (LC) and zero neutral loss tandem MS was used to remove chemical background and co-eluting interferences from the analysis of linoleic acid in cancer cell extracts. Concentration of endogenous linoleic acid was determined from back-calculation of standard calibration samples fortified with deuterium-labeled linoleic acid. No internal standard was used. LC–MS-MS analysis of the cancer cell extracts resulted in an increase in signal-to-noise ratio of 10-fold. The assay sensitivity was increased 10 times over the traditional LC–MS-MS experiment exclusively due to the new FAIMS technology.
Assay Robustness Improvement for Drug Urinalysis Using FAIMS and H-SRM on a Triple-Quadrupole Mass Spectrometer
This article demonstrates the improved robustness of a liquid chromatography–tandem mass spectrometry assay achieved by utilizing the combined selectivity of high-field asymmetric waveform ion mobility spectrometry and highly selective reaction monitoring.