A fast SPE-GC-ECD method for the analysis of PCBs in waste oil was developed. A complete profi le was obtained following SPE with a 12 minute GC run-time using a modular accelerated column heater (MACH). Full automation of the sample preparation and analysis (except sample weigh-in) enables a daily throughput of 100 samples. A wide range of concentrations can be determined using a dedicated col...

A simple and sensitive gas chromatography (GC) method is described for the trace analysis of iodide anion (iodide) in processed seaweed as an organic derivative. The method is based on the derivatization of aqueous iodide extracted from seaweed with 2-(pentafluorophenoxy)ethyl 2-(piperidino)ethanesulfonate in toluene using tetra-n-hexylammonium bromide as a phase-transfer catalyst. The resultin...

MARŠÁLEK P., SVOBODOVÁ Z. (2006): Rapid determination of methylmercury in fish tissues. Czech J. Food Sci., 24: 138–142. The aim of the present study was to develop a rapid and inexpensive method for the determination of methylmercury in fish tissues based on GC/ECD instrumentation. The new method is based on acidic digestion in hydrochloric acid and subsequent extraction with toluene. Methylme...

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...

A simple and inexpensive method based on solvent extraction followed by low temperature clean-up was applied for determination of seven pyrethroids residues in bovine raw milk using gas chromatography coupled to tandem mass spectrometry (GC-MS/MS) and gas chromatography with electron-capture detector (GC-ECD). Sample extraction procedure was established through the evaluation of seven different...

Distribution and levels of octopamine (OA), one of the biogenic amines in the invertebrate nervous system, may have significant effects on insect physiological processes including growth, feeding and reproduction. In this paper capillary gas chromatography with electron capture detection (GC-ECD) and mass selective detection (GC-MS) were used to determine the content of OA in Blattella germanic...

Polychlorinated biphenyls (PCBs) in waste oil are typically analyzed by GC-ECD or GC/MS after solid phase extraction (SPE) cleanup. However, not all problematic matrix components are completely removed during cleanup and are injected into the analytical system, thereby contaminating the column and the detector. In this application, a practical example of backflushing is presented using the Agil...

objective: the usage of pesticides has increased during the recent years. one the other hand, presence of harmful pesticides residue in rice and other food has caused a great concern among the consumers. therefore, it is important to develop some pragmatic procedures to increase the food safety along with the reduction in consumption of pesticide residues. methods: a gas chromatograph with elec...