Heizmann P, Körner J, Zinapold K
J Chromatogr. 1986 Jan 10;374(1):95-102. doi: 10.1016/s0378-4347(00)83256-9.
A high-performance liquid chromatographic method for the determination of tenoxicam in plasma has been developed. Tenoxicam was extracted from buffered plasma (pH 3 or 4, respectively) with dichloromethane and the evaporated extracts were analysed on a C18 reversed-phase column using a methanol-phosphate buffer mobile phase and with UV detection at 371 nm. The detection limit was 20 ng/ml using a 0.5-ml sample. The method is selective with respect to the 5'-hydroxy metabolite, which is present in plasma after multiple administration of tenoxicam; this metabolite may also be determined using this procedure.
