The present research describes the use of directly suspended drop microextraction and air-assisted dispersive liquid-liquid microextraction method coupled with UV-Vis spectrophotometer for the analysis of doxepin in water and biological samples. Several important parameters which influence the extraction efficiencies of these two microextraction methods, such as the kind of extracting solven...

Volatile fatty acids (VFA) are short chain aliphatic monocarboxylic acids containing from 2 to 8 carbon atoms in a molecule. They are formed in the process of anaerobic biodegradation of larger organic molecules and therefore are commonly present in municipal wastewater, effluents of food industry, livestock farm wastewater, sewage sludge, landfill leachate, feces, urine, etc. and are emitted b...

A single-drop microextraction (SDME) was developed for the analysis of volatile fatty acids (VFAs) (C2-C7) in water by gas chromatography (GC) with flame ionization detection. The significant parameters affecting the SDME performance such as selection of microextraction solvent, extraction time, stirring rate, sample pH and temperature, and ionic strength were studied and optimized. To lower li...

Two methods for the extraction, identification and quantification of the highest occurrence and lowest perception threshold off-flavours in fifteen different samples of Brazilian Pilsner beers were developed. For this purpose, headspace solid phase microextraction in combination with a gas chromatography coupled to a mass spectrometric detection (HS-SPME-GC-MS) as well as headspace extraction i...

Conventional diagnostic methods for lung cancer are unsuitable for widespread screening because they are expensive and occasionally miss tumours. Gas chromatography/mass spectrometry studies have shown that several volatile organic compounds, which normally appear at levels of 1-20 ppb in healthy human breath, are elevated to levels between 10 and 100 ppb in lung cancer patients. Here we show t...

Using Syva "EMIT" reagents and the Cobas Bio centrifugal analyzer, we have developed cost-effective assays for therapeutic drug monitoring of carbamazepine, phenobarbital, and phenytoin. With these optimized methods one can assay up to 2470 samples with a single 100-test EMIT kit with good precision and accuracy. Between-batch CVs, based on results of repeat analysis of routine patients' sample...