Validation of a LC method for the analysis of oxaliplatin in a pharmaceutical formulation using an experimental design.

A rapid and sensitive RP-HPLC method with UV detection for routine control of oxaliplatin in a pharmaceutical formulation (Eloxatin) was developed. Quantitation was accomplished with the internal standard method. The procedure was validated by linearity (correlation coefficient=0.999948), accuracy, robustness and intermediate precision. Experimental design was used during validation to calculate method robustness and intermediate precision. For robustness test three factors were considered: percentage v/v of acetonitrile, flow rate and temperature; an increase in the flow rate results in a decrease of the drug found concentration, while the percentage of organic modifier and temperature have no important effect on the response. For intermediate precision measure the considered variables were: analyst, equipment and days. The RSD value (2.27%, n=24) indicated a good precision of the analytical method.

Validation of a LC method for the analysis of zafirlukast in a pharmaceutical formulation.

A reversed-phase high-performance liquid chromatographic (HPLC) method was developed and validated for estimation of zafirlukast in a pharmaceutical formulation. Assay samples were extracted utilizing acetonitrile. Drug and internal standard were chromatographed on reversed-phase C18 columns, using mixtures of acetonitrile/water and the eluents were monitored at different wavelengths. The method was validated statistically for its linearity, accuracy, robustness and precision. Experimental design was used during validation to evaluate method robustness and for the determination of intermediate precision. Factors examined for statistical approaches include laboratory, day, analyst, instrument, different percentage of organic modifier, temperature, wavelength and flow-rate. Due to its simplicity and accuracy, the method may be used for routine quality control analysis.

Stability study of piroxicam and cinnoxicam in solid pharmaceuticals.

The pseudo-first order rate constant for the hydrolysis of cinnoxicam as a function of temperature was obtained by variable-temperature kinetic experiments. The method used is on a generalization of non-isothermal analysis, and takes advantage of the capabilities of modern data collection and processing systems. A spectrophotometric method under non isothermal conditions was carried out. The results obtained are identical to those obtained under the same conditions by using traditional constant-temperature kinetic runs. This provides the possibility of reducing the amount of time spent and chemicals usually used in collecting kinetic data in mechanistic studies in solution by an order of magnitude.

Isolation and characterization of Guiera senegalensis J.F.Gmel. active principles.

A combination of thin-layer chromatography, high-performance liquid chromatography, UV spectroscopy and NMR spectrometry techniques for analysis of flavonoid content of Guiera senegalensis J.F.Gmel. (Combretaceae) leaves is described. Four components, catechin, myricitrin, rutin and quercetin were evidenced and determined by HPLC.