Retention behaviour of a bonded reversed phase in a high-performance liquid chromatographic assay of serum theophylline

A simple, rapid assay for serum theophylline is described. Optimisation of the high-performance liquid chromatographic system has allowed the analysis of minimun sample volume (50 micronl) in the shortest time (8 min) with good between-batch precision (C.V. = 8.3%)and accuracy (recovery ca. 100%). The behaviour of theophylline and other xanthine derivatives, theobromine, caffeine and 8-chlorotheophylline, on a bonded octadecyl reversed-phase …