Enzyme immunoassay, liquid chromatography, and spectrofluorometry compared for the determination of procainamide and N-acetylprocainamide in serum.
Procainamide, an antiarrhythmic drug, and its biologically active metabolite, N-acetylprocainamide, were quantitated in serum by a commercially supplied enzyme immunoassay procedure. Replicate analyses of controls resulted in within-assay and between-assay coefficient of variation (CV) of less than 10%. Regression analyses of serum samples analyzed by immunochemical (y) and chromatographic or spectrofluorometric methods (x) gave equations with a slope of 0.99 to 1.11, y-intercept of -0.52 to -0.02, and correlation coefficient greater than 0.92. Clinical evaluation of the results indicates the respective enzyme immunoassay to be specific and sensitive for procainamide and N-acetylprocainamide. Immunochemical selectivity of the respective assay was quantitated by challenging the assay with other drugs. When the antibody reagent was crossreactive toward the other drugs, selectivity was determined to be inversely related to the concentration of the other drug.
D000120:Acecainide / Q000097:blood*; D002851:Chromatography, High Pressure Liquid; D003429:Cross Reactions; D006801:Humans; D007124:Immunoenzyme Techniques; D011342:Procainamide / Q000031:analogs & derivatives* / Q000097:blood*; D013050:Spectrometry, Fluorescence
D000120:Acecainide; D011342:Procainamide