title: Modified colorimetric method for procainamide in plasma.
abstract: We describe a modified colorimetric method for determining procainamide in plasma by use of a diazotization and coupling reaction with N-(1-naphthyl)-ethylenediamine dihydrochloride (Marshall's reagent). The sensitivity of the assay is increased twofold over the originally reported colorimetric method, and the lower limit of detection for the assay of a 1.0-ml plasma sample has been decreased to 0.5 mg/liter.
mesh_terms: D003124:Colorimetry / Q000379:methods; D005069:Evaluation Studies as Topic; D006801:Humans; D011342:Procainamide / Q000097:blood*; D012044:Regression Analysis
chemical_list: D011342:Procainamide