The determination of propoxyphene in oral fluid using solid-phase extraction and gas chromatography-mass spectrometry is described for the first time. The method employs collection of oral fluid with the Quantisal device, immunoassay screening of the specimen, confirmation of the positive screened samples after extraction using cation exchange/hydrophobic solid-phase extraction columns, optimiz...

By using a competitive solid-phase immunoassay with serotype-specific and cross-reactive neutralizing monoclonal antibodies directed at VP4 and VP7, we tested the antibody responses to some neutralization epitopes on VP4 and VP7 in individuals infected or vaccinated with rotavirus. Antibody responses to VP7 epitopes of the infecting serotype of virus were found at a high frequency in both infan...

Convenient, sensitive, and specific solid-phase immunoassays involving monoclonal antibody are described for the determination of human placental alkaline phosphatase (hPLAP). An endogenous enzyme immunoassay combined the specificity of the immunological and the enzymatic reactions. Alternatively, a solid-phase "sandwich" radioimmunoassay involving immobilized polyclonal rabbit anti-hPLAP in co...

Chlorotestosterone and its metabolites were determined in urine samples from bovine animals treated with chlorotestosterone acetate by oral and intramuscular routes. Sample preparation, involving enzymatic deconjugation and solid-phase extraction, was optimised. The effect of different enzyme preparations, pH, and time of incubation were studied. An extraction/clean-up procedure based on solid-...

BACKGROUND Monitoring of reproductive steroid hormones at the population level requires frequent measurements, hormones or metabolites that remain stable under less than ideal collection and storage conditions, a long-term supply of antibodies, and assays useful for a range of populations. We developed enzyme immunoassays for urinary pregnanediol 3-glucuronide (PDG) and estrone conjugates (E1Cs...

As a result of the studies, method direct solid-phase enzyme immunoassay (ELISA test) was optimized for detecting toxigenic strains Vibrio cholerae O1 and O139 serogroups based on monoclonal polyclonal antitoxic immunoglobulin peroxidase conjugates. The study detected following optimal parameters analysis: sensitization tablet by toxicodermia drugs diluted in phosphate-saline buffer (PBS) pH 7....

We here report a reversed-phase HPLC method for the determination of free cortisol in human urine, using methylprednisolone as the internal standard. Before chromatography, samples were extracted with a C18 solid-phase extraction column and the steroids were separated on a LiChrospher 100 C18 column with a mobile phase of methanol/acetonitrile/water (43/3/54 by vol). Linearity, precision, and a...

A solid phase, enzyme-linkcd immunoassay is described for the quantitative determination of the complex of human granulocyte elastase (EC 3.4.21.37) with αι-proteinase inhibitor. The assay employs antibody-coated test tubes and it is suitable for routine use in clinical chemistry laboratories. Data for sample stability and test characteristics are given. A reference r nge of 20—180 μg/l elastas...

Azotobacter vinelandii OP was grown to stationary phase in defined medium. The cell-free culture medium was analyzed for cytokinin content by XAD-2 and Sephadex LH-20 chromatography, thin-layer chromatography, tobacco callus bioassay, and enzyme immunoassay. Three cytokinin-active fractions were detected and tentatively identified as trans-zeatin, isopentenyladenosine, and isopentenyladenine. T...