Abstract
A simple, rapid assay for serum theophylline is described. Optimisation of the high-performance liquid chromatographic system has allowed the analysis of minimum sample volume (50 μl) 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 system suggests that the C 18 phase effects solute separation by mixed retention mechanisms rather than by pure reversed-phase chromatography. This behaviour is attributed to the participation of underivatised silanol groups in the chromatographic process, an observation corroborated by independent investigation. The mechanism of the silanol participation is difficult to rationalise; however, a normal-phase liquid partition system complies with the experimental data.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
