Multidimensional column liquid chromatography with electrochemical detection for the analysis of terbutaline in human plasma.

Because of low drug concentrations and complex nature of the sample, analytical methods with sensitive and selective detection are necessary for pharmacokinetic studies of terbutaline. Up to now, for non-radiolabelled drugs, usually only methods based on gas chromatography plus mass spectrometry have met these requirements. As an alternative, we have developed an automated method based on liquid chromatography. The necessary sensitivity and selectivity were obtained by using electrochemical detection and a microprocessor-controlled column switching system. The accuracy of the method was compared with a method based on gas chromatography plus mass spectrometry. The overall precision expressed as per cent of the mean was +/- 3.5% and +/- 2.2% at 5 and 50 pmol/mL, respectively. The total absolute recovery for terbutaline and internal standard at these concentration levels were in the range 85-106%.