Applicability of capillary gas liquid chromatography to the measurement of free fraction of disopyramide in human plasma.
A sensitive and specific capillary gas liquid chromatographic nitrogen/phosphorus selective detection technique was used to measure unbound disopyramide in human plasma. The concentration dependent protein binding of disopyramide was examined. Various concentrations of disopyramide alone ranging from 0.5 to 10.0 micrograms/ml in 0.4 ml of isotonic phosphate buffer (pH 7.4) were dialyzed for 6 hours at 37 degrees C, against 0.4 ml blank plasma from five healthy volunteers. The concentration-dependent binding of disopyramide was confirmed. The average free fraction for disopyramide at concentrations of 0.5, 1.0, 2.0, 3.0, 4.0, 5.0 and 10.0 micrograms/ml were 0.14, 0.15, 0.20, 0.27, 0.30, 0.34 and 0.53, respectively.
D002849:Chromatography, Gas; D004206:Disopyramide / Q000097:blood*; D006801:Humans
D004206:Disopyramide