The aim of the study was to develop a bioanalytical method for the determination of temozolomide (TMZ) in human plasma. Plasma concentration of TMZ was determined on a C18 column after liquid-liquid extraction. Isocratic elution was applied with the mixture of aqueous acetic acid and methanol. Theophylline was used as the internal standard. To prevent chemical degradation of TMZ at physiologica...

A simple, accurate, and precise HPLC method was developed and validated for determination of rimonabant in human plasma. Following liquid-liquid extraction, chromatographic separation was accomplished using C18 column with mobile phase consisting of acetonitrile : water (90 : 10, v/v), drug was detected at 260 nm using UVdetector. The LOD and LOQ were 3.0 and 10.0 μg/L, respectively. The method...

Article history: In this study, we established Received 11 October 2008 Accepted 25 October 2008 Available online 5 November 2008

The retention behaviour of four active compounds from Sophora Flavescens Ait using three ionic liquids as mobile phase modifiers was examined. The effect of the pH and the amount of ionic liquid modifier on the retention of these compounds was determined in methanol/water (v/v) as the mobile phase containing different ionic liquids ranging in concentration from 0.1 mmol/L to 3.0 mmol/L. The ion...

During phase I/II clinical trials of sirolimus (rapamycin; SRL), therapeutic drug monitoring was performed with a multistep liquid-liquid extraction of 1-mL aliquots of whole blood followed by reversed-phase HPLC with ultraviolet detection. Blood was sampled according to a standardized protocol and clinical status. SRL concentrations were interpolated from calibration curves with a linear range...

An accurate and simple analysis method by high-performance liquid chromatography-mass spectrometry for the riboflavin crude product of semisynthesis is established in this study. In this method, a C(18) column is used, and the mobile phase is methanol-water. Under the optimal analysis conditions established in this study, all components in the riboflavin crude product are well separated and ide...

1. Stabler, T. V., and Siegel, A. L., Rapid liquid-chromatographic/fluorometric method for taurine in biological fluids, involving prederivatization with fluorescamine. Gun. Chem. 27, 1771 (1981). Letter. 2. Larsen, B., Grasso, D., and Chung, S., A rapid method of taurine quantitation using high performance liquid chromatography. J. Chromatogr. Sci. 18, 233-236 (1980). 3. Connolly, B. M., and G...

The principles involved in the selection of solvents and the use of counter ions, together with the choice of column, for the separation of phospholipids by highperformance liquid chromatography (HPLC) are described.

Aerobic biodegradation behavior of nonylphenol propoxylates was investigated using dispersive liquid-liquid microextraction as a simple and fast technique for sample preparation. The developed method proved to be efficient for the isolation and concentration of nonylphenol propoxylates before their quantification with the use of high performance liquid chromatography. The primary biodegradation...