SIMPLE AND RELIABLE GAS-LIQUID-CHROMATOGRAPHIC ASSAY FOR UNDERIVATIZED THEOPHYLLINE IN PLASMA USING AN ORGANIC-NITROGEN SPECIFIC DETECTOR

Plasma levels of the bronchodilator theophylline (1,3-dimethylxanthine) are now measured routinely in many laboratories and many methods have been described. There is a need for a reliable GLC procedure that possess the advantages of speed, simplicity and sensitivity for pediatric samples and which also eliminates the potential problems associated with derivative formation. A system that fulfills these criteria is described. This GLC procedure is both reliable and simple to perform. It is sufficiently sensitive to measure theophylline in pediatric samples, a large number of determinations can readily be carried out in 1 batch and a derivatization step is not required. The system is entirely suitable for the routine measurement of theophylline in plasma.