Bioanalytical method development and validation for a large peptide HIV fusion inhibitor (Enfuvirtide, T-20) and its metabolite in human plasma using LC-MS/MS.

A method for measuring a human immunodeficiency virus (HIV) cell membrane fusion inhibitor (T-20/Ro 29-9800) and its metabolite (M-20/Ro 50-6343) in human plasma by liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed. The relatively large peptide analytes and their corresponding deuterated (d(10)) peptides used as internal standard were isolated from plasma by protein precipitation with two volumes of acetonitrile to plasma. A large pore size reversed-phase C(18) column was employed to elute the peptides.

A HPLC method for the determination of 9-cis retinoic acid (ALRT1057) and its 4-oxo metabolite in human plasma.

A HPLC method was developed and validated for the quantitation of 9-cis-retinoic acid (ALRT1057) and its major metabolite, 4-oxo-9-cis-retinoic acid (LG100182) in human plasma. Samples were buffered and extracted with methyl-tert-butyl-ether. The analytes and an I.

Development and validation of column-switching high-performance liquid chromatographic methods for the determination of a potent AII receptor antagonist, TCV-116, and its metabolites in human serum and urine.

Column-switching HPLC methods have been developed and validated for the determination of a new antihypertensive prodrug, TCV-116 (I), and its metabolites, CV-11974 (II) and CV-15959 (III), in human serum and urine. Initial sample cleanup was achieved by extracting the analytes into an organic solvent. After chromatographing on an ODS column with a mobile phase consisting of acetonitrile and an acidic phosphate buffer, the zone of the analyte's retention was heart-cut onto a second ODS column with a mobile phase of acetonitrile and a phosphate buffer at a higher pH.

Development and validation of an LC method for the quantitation of carbenicillin in human serum.

An LC method for the quantitation of carbenicillin in human serum has been developed and validated. After protein precipitation with acetonitrile and evaporation, the residue was taken up by citric acid at pH 1.9.

Sensitive and specific radioimmunoassays for opiates using commercially available materials. I: Methods for the determinations of morphine and hydromorphone.

Sensitive and specific radioimmunoassay (RIA) methods for the analysis of morphine and hydromorphone in human plasma samples using commercially available materials were developed. The limit of quantitation was 0.3 ng/mL of plasma for morphine and 50 pg/mL of plasma for hydromorphone.