High-performance liquid chromatographic analysis of three macrolide antibiotics in pharmaceutical formulations and in human plasma

A high-performance liquid chromatographic method, for the determination of three macrolide antibiotics [roxithromycin [RXE], erythromycin base [E] and erythromycin ethylsuccinate [EES]], is presented. Study of the optimum condition for separation and quantitation of these antibiotics indicated that chromatography is performed in the reversed-phase mode using a C-18 column at a temperature of 40C. The strength of phosphate buffer can be used to control selectivity of the separated compound. The addition of isopropanol to the mobile phase improves peak shapes for the compounds of interest. Validation data for the studied antibiotics is done on spiked human plasma samples after extraction by adopting a rapid and simple procedure. The intra- and inter-assay coefficients of variation were less than 5% for the spiked plasma and pharmaceutical dosage forms

Determination of trimebutine in human plasma by high perfor-mance liquid chromatography with ultra-violet detection

Simple and sensitive HPLC method for the determination of trimebutine in human plasma was described. For the best separation, a suitable mobile phase consisted of 0.05 M phosphate buffer adjusted to pH 3.5 with phosphoric acid-methanol-isopropanol [32: 58: 10 by volume] was investigated. The mobile phase was prepared to contain 0.006 g% of sodium lauryl sulfate. The drug after extraction from plasma was chromatographed on a C-18 column. Trimebutine and internal st and ard, propyl para-hydroxybenzoate sodium salt [PPB], were detected at 265 nm. Extraction of the drug from plasma was developed to be complete, simple and non-destructive for the active components. The intra- and inter-assay coefficients of variation were less than 5%. The detection limit [signal-to-noise ratio = 3] was 0.5 mug/ml for plasma and the linearity was valid up to 12 mug/ml. The assay was successfully applied to study the bioequivalency of two commercial products containing trimebutine maleate. The tested tables were bioequivalent to the reference tablets