Improved high-performance liquid chromatographic detection of paclitaxel in patient's plasma using solid-phase extraction, and semi-micro-bore C₁₈ separation and UV detection

Although a number of analytical methods for taxanes have been published, none of them are sufficiently suitable for use in a medical setting. In this study, we established an improved analytical HPLC/UV detection method using a Sep-Pak C₁₈ cartridge for extraction and a semi-micro-bore column for separation. This method employed here reduced chromatographic background signals, and allowed a more sensitive analysis of taxanes in human blood sample. The recovery of taxanes after the solid-phase extraction procedure was over 90%. Chromatographic separation of paclitaxel and docetaxel was achieved within 30 min with no interference peak by a semi-micro-bore column, packed either with C₁₈ (Wakosil 5C18 RS) or pentafluorophenyl (Curosil/Taxol) materials. The method was reproducible with coefficients of variation less than 6%. This analytical procedure was simple and sensitive with lower quantification limit of 3 ng/ml. The improved sensitivity achieved by the popular HPLC/UV apparatus, which is available in hospitals, would vouch safer and more efficient therapy with taxane.