A sensitive electron-capture gas-liquid-chromatographic method for the determination of sub-nanogram quantities of prostaglandin F(2alpha) was developed. The method is based on the sub-microgram scale conversion of the prostaglandin into the electron-capturing pentafluorobenzyl ester, and analysis of the latter as the tris-trimethylsilyl ether. The lower limit of detection was 12.5pg of the est...

A method for the assay of acidic catecholamine metabolites in biological fluids using capillary gas chromatography--electron-capture negative-ion mass spectrometry is described. The method combines acetylation of phenolic hydroxy groups in buffered aqueous solution followed by pentafluorobenzyl ester formation and acetylation of aliphatic hydroxy groups under anhydrous conditions. The resulting...

A rapid multiresidue method has been developed for the analysis of 20 organochlorine pesticides (OCs) in fruits and vegetables. The method is based on a modified QuEChERS procedure employing acetonitrile for extraction and partition. Dispersive solid-phase extraction (dSPE), containing primary and secondary amine (PSA) and graphitized carbon black (GCB), was used for cleans-up. Analytical deter...

Management of cocoa plantation field relied on the use of pesticides over the years; hence, the fate of such chemicals is one of the most debated issues among the stakeholders. Young and old cocoa plantation fields from 4 major cocoa producing States in Nigeria were selected as the study area. Eight composites soil samples collected from 3 portions of 6 transect measured area (100 x 50m) of the...