Determination of noretisterone in tablets by differential pulse polarography

Abstract

A rapid differential pulse polarographic method for quantitative determination of norethisterone (NE) in a tablet is described. The procedure involves disintegrating the tablet with a few drops of distilled water inside a 100 ml volumetric flask, addition of 40 ml methanol, addition of 20 ml .2 M tetramethyl ammonium bromide solution, and dilution to the mark with distilled water. 25 ml of the solution are then transferred to a polarographic cell, dissolved air is removed by bubbling nitrogen through the liquid, and the differential pulse polarographic peak is recorded. A 10 ppm standard sample solution, with excipients corresponding to 1 tablet, and a blank solution with excipients only are both tested in the same manner. The amount of NE can then be calculated as the ratio of the peak currents of the tablet solution to those of the standard solution measured against those of the blank solution. Peak current increases linearly as a function of concentration of NE over the range 2-200 ppm.