Electron-capture GLC determination of bromhexine in human plasma

A specific and sensitive GLC analysis of bromhexine in human plasma is described. After addition of the internal standard and an aqueous triethanolamine solution, bromhexine is extracted at alkaline pH into n-hexane, transferred to an acidic aqueous solution, and back-extracted into n-hexane after alkalinization. Both compounds are derivatized with trifluoroacetic anhydride and quantified by GLC using , 63Ni-electron-capture detector. The method has a sensitivity of approximately 1.0 ng/ml of plasma. Linearity of plasma working curves was good. The extraction recovery from spiked plasma was 90.1 +/- 5.68% (SD). The within-run and within-day precisions (CV) were 6.0% (4.3 ng/ml, n = 8) and 8.6% (11.0 ng/ml, n = 13), respectively. The procedure was applied successfully to measurement of the plasma concentration-time profile in a human volunteer after oral drug administration.