Background: Saliva is an alternative biological matrix in drug testing. It has several advantages in comparison with other biological fluids such as blood and urine. Collection of saliva is simple, noninvasive and can be controlled under direct observation in drug abusers, or opium addicts. Methods: In the present study we report our experience with saliva collection, liquid-liquid extraction a...

We compared the performance of gas chromatography time-of-flight mass spectrometry (GC-MS) and comprehensive two-dimensional gas chromatography mass spectrometry (GC×GC-MS) for metabolite biomarker discovery. Metabolite extracts from 109 human serum samples were analyzed on both platforms with a pooled serum sample analyzed after every 9 biological samples for the purpose of quality control (QC...

Pesticide residue analysis in medicinal herbs is a challenging task because of the matrix effect and its influence on quantitative despite continuous development several new analytical methods instrumentations. In this study, modified QuEChERS method was developed for indoxacarb by using conventional instrument, gas chromatography micro-electron-capture-detector (GC–μECD), comparing it with chr...

Utilizing chemical derivatization (CD) to improve gas chromatographic (GC) and GC-mass spectrometric (MS) analysis of drugs has been abundantly studied and widely practiced, while in liquid chromatography (LC) and LC-MS, application of CD approaches is still at an early stage. Silylation, acylation, and alkylation are common CD reactions, long adopted by GC and GC-MS (including GC-MS/MS) method...

Fast gas chromatography–mass spectrometry (GC–MS) has the potential to be a powerful tool in routine analytical laboratories by increasing sample throughput and improving laboratory efficiency. However, this potential has rarely been met in practice because other laboratory operations and sample preparation typically limit sample throughput, not the GC–MS analysis. The intent of this article is...

Although gas chromatography–triple quadrupole mass spectrometry (GC-MS/MS) has been applied to the determination of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) in various food samples, there is insufficient evidence evaluate its equivalence with chromatography–high resolution (HRMS). In present study, two GC-MS/MS instruments different ion sources (advanced electron ionization [EI] a...

Female boat-tailed grackles poisoned with 3-chloro-p-toluidine hydrochloride (CPTH) were analyzed by necropsy and gas chromatography–mass spectrometry (GC-MS). The necropsies identified the presence of a white precipitate in the pericardium, which had been previously reported as a characteristic of CPTH-exposed birds. The GC-MS method, which utilized deuterated CPTH as a surrogate, quantified C...

Identifying non-annotated peaks may have a significant impact on the understanding of biological systems. In silico methodologies have focused on ESI LC/MS/MS for identifying non-annotated MS peaks. In this study, we employed in silico methodology to develop an Isotopic Ratio Outlier Analysis (IROA) workflow using enhanced mass spectrometric data acquired with the ultra-high resolution GC-Orbit...