title: Quantitative high-performance liquid-chromatographic method for determining disopyramide (Norpace) in serum.
abstract: We report a high-performance liquid-chromatographic method for measuring disopyramide (Norpace, Searle) in serum. The drug is extracted from 0.5 ml of serum into chloroform containing the internal standard p-chlorodisopyramide, separated on a reversed-phase octadecylsilyl column at room temperature, and detected at 254 nm. The method is sensitive to 0.2 mg of disopyramide per liter, with a linear response to at least 10 mg/liter. Within-day precision (CV) for frozen serum pools is 8.3 (n = 21) and (n = 22) at mean concentrations of 2.6 and 5.9 mg/liter, respectively. Day-to-day precision (CV) is 9.4 (n = 80) and 9.3 (n = 29) at mean concentrations of 2.8 and 6.7 mg/liter, respectively. Recoveries for disopyramide in serum averaged 98% over the linear range when compared against an aqueous standard taken through the entire analytical procedure. The method is relatively specific, as evidenced by interference studies with over 85 drugs.
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004206:Disopyramide / Q000097:blood*; D006801:Humans; D011725:Pyridines / Q000097:blood*; D012015:Reference Standards; D013997:Time Factors
chemical_list: D011725:Pyridines; D004206:Disopyramide