Analysis of Melatonin in Dosage Formulation by Capillary Electrophoresis.

A simple, fast, and reproducible capillary electrophoretic method is developed and validated for analysis of melatonin in pharmaceutical preparations. The CE method was developed by using a fused silica capillary (60 cm×50 µm I.D.), phosphate buffer (50 mM, 3.0 pH) as the background electrolyte (BGE), 20 kV applied voltage with UV detection at 214 nm, and at a working temperature of 23±1°C. Linearity was observed in the concentration range from 10 to 100 µg/L with a correlation coefficient (R2) of 0.9996. The limits of detection and quantification achieved were 10 and 15 µg/mL, respectively. The percentage recovery of melatonin from pharmaceutical preparations was 95.0. Validation parameters prove the precision of the method and its applicability for the determination of melatonin in pharmaceutical tablet formulations. [ABSTRACT FROM AUTHOR]