Liquid chromatography-tandem mass spectrometric assay for the non-nucleoside reverse transcriptase inhibitor rilpivirine in human plasma.

An analytical method based on liquid chromatographic-tandem mass spectrometry (LC-MS/MS) was developed for the determination of the non-nucleoside reverse transcriptase inhibitor rilpivirine in human plasma using nevirapine as an internal standard. Analyte and the internal standard were extracted from human plasma by liquid-liquid extraction. The reconstituted samples were chromatographed on a C(18) column using a mixture of acetonitrile and 0.

Simultaneous determination of sitagliptin and simvastatin in human plasma by LC-MS/MS and its application to a human pharmacokinetic study.

A simple, rapid and sensitive liquid chromatography-tandem mass spectrometric (LC-MS/MS) assay method has been developed and validated for simultaneous quantification of sitagliptin and simvastatin in human plasma. Carbamazepine was used as an internal standard (IS). The analytes and IS were extracted from the human plasma by liquid-liquid extraction technique.

Influence of some bioflavonoids on the transport of nitrendipine.

Flavonoids form a large class of phenolic substances widely distributed in nature and exhibit several biological effects. P-glycoprotein is part of a large family of efflux transporters found in the gut, gonads and other organs. Male albino rats were used for this study.

Study on the influence of silymarin pretreatment on metabolism and disposition of metronidazole.

A clinical study was undertaken in 12 healthy volunteers. At first, subjects received metronidazole (CAS 443-48-1; a substrate for cytochrome CYP3A4 and CYP2C9) alone at a dose of 400 mg every 8 h for 3 days. On day 4, blood and urine were collected at different time points and metronidazole levels were measured.

Validated high performance liquid chromatographic method for simultaneous determination of phenytoin, phenobarbital and carbamazepine in human serum.

A high performance liquid chromatographic (HPLC) method for the simultaneous determination of phenytoin (CAS 57-41-0), phenobarbital (CAS 50-06-6, phenobarbitone) and carbamazepine (CAS 298-46-4) is described. The serum was extracted with ethyl acetate, the dried extract was reconstituted in mobile phase and the aliquot was injected. The eluent drugs were detected at 230 nm.

Paracetamol metabolism in Indian population.

To investigate the profile of paracetamol (CAS 103-90-2, Calpol) metabolism in Indian population and to compare with the profiles of studies conducted in other populations, a study was conducted in 100 healthy male human volunteers. After an overnight fast, the volunteers were administered an oral dose of 1 g of paracetamol, urine was collected up to 8 h and samples were analyzed by high performance liquid chromatography for the estimation of urinary recovery of paracetamol and its metabolites, i.e.