Captopril is widely used in the treatment of hypertension. Given its short half-life, captopril was formulated into mucoadhesive tablet form to reduce the frequency of drug use. Therefore, assay and dissolution are indispensable in assuring drug quality. This study aimed to obtain a valid method for the determination of assay and the dissolution of captopril in mucoadhesive tablet form. The analysis was carried out using a high-performance liquid chromatograph equipped with a LiChrospher® 100 RP-8 (250 x 4.6 mm i.d., 5 µm) column. The mobile phase was methanol and water containing 0.001% of phosphoric acid pH 2.3 (1:1) at a flow rate of 1.0 mL/min, and the detector was set at 220 nm for the assay and at 205 nm for the dissolution. The injection volume was 20 µL. The methods were validated as per ICH Guideline Q2(R1). The assay and dissolution were considered specific as evidenced by 0.1% and 0.0% interference values, respectively. The average recovery of the assay method was 100% at the concentrations of 30, 50, and 65 ppm, whereas the dissolution method recovered 99% of the drug at 5.6, 22.2, 27.8, and 36.1 ppm. The RSD values for precision of the assay and dissolution methods were 1.5% and 1.7% for six time sample preparations, whereas the RSD values of the ruggedness study performed in 3 days by two analysts were 1.6% and 2.7%. The methods were linear, with an r2 value of 0.9993 at 5-75 ppm for the assay and 0.9992 at 5.6-41.7 ppm for the dissolution. The results suggest that the methods are valid and can be applied to analyze captopril mucoadhesive tablet.
Key words: captopril, mucoadhesive tablet, assay, dissolution
|
