Spectrophotometric determination of minocycline hydrochloride with p-carboxyphenylfluorone and titanium (IV)

Abstract

A spectrophotometric method for the determination of minocycline hydrochloride (MC) was established with p-carboxyphenylfluorone (PCPF) and titanium (IV). Beer's law was obeyed in a concentration range 5∼25 μg of MC in 10 ml of final solution. The apparent molar absoptivity of the proposed method, which does not require an extraction procedure, is 1.2 × 10⁵ l mol^-1 cm^-1 at 580 nm. The relative standard deviation for five replicate determinations for 12.3 μg of MC was 2.1%. The proposed method was then applied to the assays of MC in pharmaceutical preparation (tablet), and the results were satisfactory.