Development of a Validated Colorimetric Assay Method for Estimation of Amikacin Sulphate in Bulk and Injectable Dosage Form

Amikacin sulphate is devoid of any chromophore and/or conjugated system prerequisite for UV and florescent light detection (FLD). Hence, there is a need of simple and reliable methods for introducing chromophore in the structure of amikacin sulphate for its determination using UV and FLD. Therefore, the present study describes the development and validation of a simple, economical and fast colorimetric method for estimation of the drug. The analyte and aqueous ninhydrin solution upon heating for 2-5 min produced the Ruhemann purple colored drug-derivative which was detected at two wavelengths, 400 nm and 567 nm. Beer’s law was obeyed over the concentration ranges from 0.417 mg/ml to 2.500 mg/ml. The method was found to be reliable (95.07 – 100.52 % recovery at 400 nm and 96.04 – 99.89 % at 567 nm), repeatable intraday accuracy (95.07 – 100.52 % at 400 nm and 96.04 – 99.84 % at 567 nm) and reproducible -inter day accuracy (95.25– 99.91 % at 400 nm 96.52 – 99.89 % at 567 nm) with relative standard deviation less than 5 %. The results of the present study indicate that the method is easy to perform, specific and sensitive, and suitable to be used for the determination of amikacin sulphate in bulk and injectable dosage forms using less expensive/laborious derivatization.