A simple, reproducible and rapid gas chromatographic method for precise determination of valproic acid (VPA) in human plasma has been developed. Total time for sample preparation and GC analysis is less than 45 min. After plasma protein precipitation, VPA was extracted into chloroform with suitable recovery. By using Stabilwax®<span styl...

A "high-performance" liquid-chromatographic procedure for 5-hydroxy-3-indoleacetic acid is described and compared with a colorimetric method in which 1-nitroso-2-naphthol is used. The analyte and an internal standard, p-nitrobenzoic acid, were extracted into diethyl ether from urine at pH 4.0 (acidified with HCl) to which sodium chloride had been added, and the ether was back-extracted with ace...

This work is concerned with the development and validation of two accurate, precise and specific spectrophotometric and chromatographic methods for analysis of Phenylepherine (PE), Lidocaine (LC) and Thiomersal (TM) in their ternary mixture and in Chromoderm® solution. The developed spectrophotometric method is the mean centering of ratio spectra (MCR) spectrophotometric method that depends on ...

We describe a sensitive, precise high-pressure liquid chromatographic method in which 5-(p-methylphenyl)-5-phenylhydantoin is used as the internal standard for simultaneous determination of diphenylhydantoin, phenobarbital, and primidone in whole blood and plasma. These anticonvulsant drugs are well separated from each other and from normal blood constituents in less than 10 min. The lower limi...