A novel analytical method, using gas chromatography-electron capture detection (GC-ECD) and GC-mass spectrometry detection (MS), was developed for the qualitative and quantitative measurement of pentachlorophenol in meat and fish. The analyte was extracted by methanol-2% trichloroacetic acid (3/1, v/v) with accelerated solvent extraction (ASE). The eluted fraction was evaporated and derivatized...

Solid waste, including petroleum based waste oils, transformer oil or mineral oil are screened for the presence of polychlorinated biphenyls (PCBs). The analysis is typically performed by GC-ECD or GC-MS after clean-up using column chromatography, solid phase extraction (SPE), or dispersive solid phase extraction (d-SPE). Clean-up on silica or acidified silica removes polar constituents that ca...

A new electron capture detector (ECD) for the Agilent 6890 Series gas chromatograph (GC) allows very sensitive detection of nitroaromatic compounds at low picogram levels with a linear response over three orders of magnitude. Analysis of Nitroaromatics and Nitro-Polycyclic Aromatic Hydrocarbons by Capillary Gas Chromatography with the Agilent 6890 Micro-ECD This application note describes the p...

Abstract. Nitrous oxide (N2O) is one of the important greenhouse gases. N2O emissions from anthropogenic sources are approximately 7-8 million tones N/yr worldwide and 70% of these emissions are caused by crop and animal production. In this study, direct N2O production from dairy cattle (enteric fermentation) and feces/urine temporarily stored in two freestall dairy barns were measured with 1) ...

The objectives of this work assignment were to evaluate ELISA screening methods and determine whether these methods indicate effectively those microenvironments where high exposure to polycyclic aromatic hydrocarbons (PAH) or other semivolatile organic compounds (SVOC) is likely. Four commercially available assay kits for PAH, carcinogenic PAH (C-PAH), 2,4-D, and pentachlorophenol (PCP) were ev...

The GC of halides (chloride, bromide and iodide) using phenylboronic acid (PBA), 4-bromophenylboronic acid (BPBA), 3, 5 bis (trifluoromethyl) phenylboronic acid (FPBA) and 2,4- dichlorophenylboronic acid (CPBA) as derivatizing reagents are compared. The reactions are carried out in the presence of mercuric salts. The detection systems used are FID and ECD. The thermal analysis of the compou...

Concentrations of halogenated volatile organic compounds VOCs were determined by gas chromatography GC with an electron-capture detector GC-ECD and by gas chromatography with mass spectrometry GC-MS in 109 groundwater samples from five study areas in the United States. In each case, the untreated water sample was used for drinking-water purposes or was from a monitoring well in an area near a d...

Background Post translational modifications regulate several signalling pathways and glycosylation is emerging as a key player in this regulatory process. Glycosylation of cell surface receptors modulate the downstream signalling pathway and when altered causes a change in the normal physiology of the cell [1]. Guanylyl cyclase C (GC-C) belongs to a group of membrane bound receptors that produc...