Electron-capture capillary gas chromatographic determination of phenylpropanolamine in human plasma following derivatization with trifluoroacetic anhydride.

A capillary gas chromatographic analysis of phenylpropanolamine in human plasma, following extraction and derivatization with trifluoroacetic anhydride, is presented. Using an electron-capture detector, the method was sensitive enough to quantitate as little as 1 ng of drug/mL of plasma. The coefficient of variation from 5-262 ng/mL varied between 5.6 and 1.6%, respectively. Plasma concentration data following one 25-mg dose of phenylpropanolamine hydrochloride in four healthy volunteers illustrates the suitability of this analytical method for monitoring plasma levels after oral administration of a typical dosage form.