Original Articles
Yasmeen H. Muhamad
Abstract
New turbidimetric methods were developed for the determination of Promethazine Hydrochloride and Codeine Phosphate in pharmaceutical preparation. The procedure is based on the precipitation of Promethazine and Codeine as ion pair complex by reaction with sodium tungstate in acidic media to formation a white precipitate. The experimental parameters such as reagent concentration, colloid protection, time effect…etc, have been investigated in this paper. The results show that the calibrations graph were constructed to form linear range (0.03-2.0) and (0.05-3.5) mmol.L-1 while the correlation coefficient are 0.9985 and 0.9951 for Promethazine and Codeine respectively. Also, Limit of Detections for stepwise dilution of minimum concentration in the linear range of the calibration graph is 1×10-5 (PMH) and 2.5×10-5 (COP) mol.L-1. While repeatability (RSD%) of the proposed method < 2.5% for both of Promethazine and Codeine. A comparison was achieved between the developed procedures and the official method via use the paired t-test. The proposed methods were successfully applied in the determination of drugs in different pharmaceutical tables.