Preparation of sample solutions
A 10−3 M of each drug was prepared by dissolving the calculated weight in a 100-ml calibrated flask and completed to the mark with water.
Solutions of Cd2+, Co2+, Mn2+ and Zn2+ thiocyanate complexes (0.010 M) are prepared by dissolving the accurately weighed amount of the metal ion salts and potassium thiocyanate in the proper volume of bidistilled water. Also 0.10 M of ammonium reineckate and/or sodium cobaltinitrite was freshly prepared by dissolving the accurate weight of salts in 100 ml-calibrated flask with water. Working solutions of lower concentrations were prepared by appropriate dilution of the standard solutions.