Spectrophotometric Determination of Some Antiulcerative Drugs in Pharmaceutical Dosages

Resumo

The aim of this work is to develop cheap, safe, rapid, reliable and reproducible spectrophotometric method for the assay of some antiulcerative drugs namely Omedar, Nadine and Rantag in their pharmaceutical dosages, using methyl red (MR) as a chromogenic reagent. The proposed method is based on the reaction of each of the three drugs with MR at pH 3.0. The optimum analytical variables have been investigated carefully. The maximum absorbance was obtained at 405 nm with absorptivity of 1.35 × 10⁴ L/mol cm. Beer’s law is obeyed in the range of concentration of 0.5–15 μg/mL for ranitidine (active ingredient) content in the studied drugs. The limits of detection and quantification of the drug active ingredient were 0.05 and 0.13 μg/mL, respectively, with a linear regression correlation coefficient of 0.998, and recovery was in the range 99.91–100.48%. Effects of pH, temperature, standing time and MR concentration on the determination of ranitidine hydrochloride of the drugs have been examined. This method is simple and can be used for the determination of ranitidine in the pharmaceutical dosages of antiulcerative drugs.