Colorimetric determination of procainamide in injectable preparations.
A simple, rapid colorimetric method is described which determines procainamide in commercially available, injectable solutions. It is based on complexing the drug with cupric ion and then measuring the absorption at 380 nm. The reaction is fast and the metal-drug ratio in the complex is 1:1. The pH optimum for maximum reaction is 4.0-4.5 which is maintained by an acetate buffer. Linear standard curves were obtained from 1.52 to 6.06 mg/mL. Analysis of 29 commercial samples resulted in an average of 97.3% of the label claim.
D000120:Acecainide / Q000032:analysis; D055598:Chemical Phenomena; D002621:Chemistry; D003124:Colorimetry / Q000379:methods; D003300:Copper; D006863:Hydrogen-Ion Concentration; D007267:Injections; D011342:Procainamide / Q000032:analysis*
D003300:Copper; D000120:Acecainide; D011342:Procainamide