Two derivative spectrophotometric determinations of indapamide in pharmaceutical dosage forms

Simple, fast and reliable derivative spectrophotometric methods were developed for determination of indapamide in bulk and pharmaceutical dosage forms. The solutions of standard and the sample were prepared in methanol. The quantitative determination of the drug was carried out using the first-derivative values measured at 252.8 nm ( N=6) and the second-derivative values measured at 260.4 nm ( N=9). Calibration graphs constructed at their wavelengths of determination were linear in the concentration range of indapamide using peak to zero 1.00–30.00 μg ml −1 for first-derivative and 1.00–35.00 μg ml −1 for second-derivative spectrophotometric method. The developed methods were successfully applied for the assay of pharmaceutical dosage forms which do not require any preliminary separation or treatment of the samples. The details of the statistical treatment of analytical data are also presented. The results obtained from two derivative spectrophotometry were compared with a spectrophotometric method reported in literature and no significant difference was found statistically.