in this study, a simple and reliable method by gas chromatograph–mass spectrometry (gc–ms) was developed for the fast and regular identification of 3, 4-mdma impurities in ecstasy tablets. in so doing, 8 samples of impurities were extracted by diethyl ether under alkaline condition and then analyzed by gc–ms. the results revealed high mdma levels ranging from 37.6% to 57.7%. the gc-ms method sh...

Sample Types LC/MS systems facilitate the analysis of samples that traditionally have been difficult to analyze. Despite the power and usefulness of gas chromatography/mass spectrometry (GC/MS), many compounds are impossible to analyze with GC/MS. LC/MS significantly expands the effective analytical use of mass spectrometry to a much larger number of organic compounds. Gas chromatography and GC...

The complex nature of botanicals and essential oils makes it difficult to identify all of the constituents by gas chromatography/mass spectrometry (GC/MS) alone. In this paper, automated sequential, multidimensional gas chromatography/mass spectrometry (GC-GC/MS) was used to obtain a matrix-specific, retention time/mass spectrometry library of 190 juniper berry oil compounds. GC/MS analysis on ...

This review aims at summarizing the most recent updates in the field of acrylamide (AA) formation (mechanism, conditions) and the determination of AA in a number of foods (fried or baked potatoes, chips, coffee, bread, etc). The methods applied for AA detection [Capillary Electrophoresis-Mass Spectrometry (CE-MS), Liquid Chromatography-Mass Spectrometry (LC-MS), Non-Aqueous Capillary Electropho...

The most effective methods of analysis of organic compounds in biological fluids are coupled chromatographic techniques. Capillary gas chromatography/mass spectrometry (GC-MS) allows the most efficient separation, identification and quantification of volatile metabolites in biological fluids. Liquid chromatography-mass spectrometry (LC-MS) is especially suitable for the analysis of non-volatile...

There are well over 500 registered pesticides worldwide for use in agricultural regions and new agrochemicals are introduced to the marketplace continuously. This chapter deals with the chemical analysis methods for the main pesticide chemical classes that are most frequently analyzed with gas chromatography (GC) or liquid chromatography (LC) coupled to mass spectrometry (MS). GC amenable pesti...

Oral fluids are being used as an alternative matrix to urine for drug testing. Oral fluid is considered to be less invasive and much more difficult to adulterate than urine samples. Samples of oral fluid are typically screened by an ELISA immunoassay method. Those found to be positive must be further analyzed with a mass spectrometry confirmation technique. The confirmation technique must be ab...

The essential oil in leaves of Polygonum minus Huds., a local aromatic plant, were identified by a pipeline of gas chromatography (GC) techniques coupled with mass-spectrometry (MS), flame ionization detector (FID) and two dimensional gas chromatography time of flight mass spectrometry (GC x GC-TOF MS). A total of 48 compounds with a good match and high probability values were identified using ...

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...

An overview of chromatography-mass spectrometry coupling is presented here, focussing mainly on possibilities offered by this detection technique. GC-MS and HPLC-MS are the two most often used variants, which have quite different characteristics. Various mass-spectrometric possibilities are briefly discussed: ionization techniques, determination of elemental formulas, structural information and...