Determination of organic acids in urine by solid‐phase microextraction and gas chromatography–ion trap tandem mass spectrometry previous ‘in sample’ derivatization with trimethyloxonium tetrafluoroborate

Abstract

A method for the determination of the organic acids directly in the urine employing derivatization with trimethyloxonium tetrafluoroborate as a methylating agent and sequential extraction by head space and direct immersion/solid phase microextraction is reported. Furoic acid, hippuric acid, methylhippuric acid, mandelic acid, phenylglyoxylic acid and trans, trans muconic acid contained in urine and proposed by the American Conference of Governmental Industrial Hygienists as biological exposure indices were determined after a fast and economically convenient preparation step and sensitive gas chromatography-ion trap-mass spectrometry/tandem mass spectrometry analysis. Urine is rather a complex sample and hence the acquisition method required specific GC-MS instrumentation capable of supporting the changeover, fully automated during a single chromatographic separation, from mass to tandem mass spectrometry and both chemical and electron ionization modes. The automation of the analytical method provides a number of advantages, including reduced analysis time for both routine analysis and method development, and greater reproducibility. The equilibrium and kinetics of this substances vs head space/direct immersion-solid phase microextraction were investigated and evaluated theoretically.

Polymerization Inhibitors and Promoters for Unsaturated Polyester Resins; Use of Solid Phase MicroExtraction and Gas Chromatography Coupled to Mass Spectrometry for the Determination of 4-tert-Butyl Catechol and Acetylacetone

“…Therefore, the constant of distribution estimated from physicochemical tables or by using the structural unit contribution method can anticipate trends in SPME analysis. The KH of the TBC-dimethylether, acetylacetone-PFB-oximes and TBBC-methyl-bis-oxime derivatives were 1.3, 71 52 and atm cm 3 /mol, which were in agreement with that reported by Pacenti et al [34], and indicated that HS-SPME is efficient for compounds with the KH higher than 0.17 atm cm 3 /mol ( Table 1).…”

Studies on styrene concentration in drinking water and hot beverages in some settings

“…Modern high-performance liquid chromatography (HPLC) with UV detection (Bourque et al, 1994;Fujii et al, 1999;Inoue et al, 1991), gas chromatography (GC) with flame ionization detection (Chakroum et al, 2008;Kataoka et al, 1991), and high-performance chromatography with mass spectrometry (Pacenti et al, 2008;Marais and Laurens, 2005) were performed for evaluating styrene. The level of styrene present in food and drinks depend on many factors such as heat, pH, fats, and the time of storage.…”

Analysis of Matrine Alkaloids in Human Urine by Hollow Fiber Liquid-phase Microextraction with High-performance Liquid Chromatography

“…Traditional methods, such as liquid-liquid extraction (LLE) 9 and solid phase extraction (SPE), 10 are tedious, time-consuming and consume large amounts of solvent. Recently, new microextraction techniques such as solid phase microextraction (SPME), 11,12 and liquid phase microextraction (LPME) 13 have been developed because they are simple, fast and solvent-free or with less consumption of organic solvent. Among these techniques, liquid phase microextraction using a hollow fiber (HF-LPME) 14 provides a simple, effective, economic and environmentally benign extraction method.…”