Simultaneous determination of omeprazole and its metal complexes by reversed-phase high performance liquid chromatography in pharmaceutical formulations

الملخص EN

A sensitive, precise, selective and accurate reversed-phase high-performance liquid chromatographic (RPHPLC) method has been developed for the simultaneous determination of omeprazole in Risek ® capsules.

Omeprazole and the internal standard, diazepam, were separated by Shim-pack CLC-ODS 0.4 × 25 cm, 5 m particle size column.

The mobile phase was Methanol-Water (80 : 20, v /v), pumped isocratically at ambient temperature.

Analysis was run at a flow rate of 1.0 mL / min at a detection wavelength of 302 nm.

The method was specific and sensitive with a detection limit of 3.5 ng / mL at a signal-to-noise ratio of 4 : 1.

The limit of quantification was set at 6.25 ng / mL.

The calibration curve was linear over a concentration range of 6.25-1280 ng / mL.

Precision and accuracy, demonstrated by within-day, between-day assays, and inter-operator assays were lower than 10%.

The in vitro availability of omeprazole in presence of manganese, cobalt, nickel, copper and zinc was studied by this method.

Recovery of omeprazole in presence of various metals was from 41% to 74 .%