Rapid and specific precolumn extraction high-performance liquid chromatographic assay for bupivacaine in human serum

A rapid and specific HPLC assay for quantiative determination of bupivacaine in human serum is described. The technique incorporates an on-line sample clean-up system followed by reversed-phase chromatography with UV detection. The proposed method uses a column-switching technique and protein-coated Lichrosorb RP-8 as a precolumn together with Lichrosorb RP-18 as an analytical column. The total run time for an injection of serum sample was 10 min. This procedure offers a sensitive assay without the need for time-consuming extractions. The average bupivacaine recoveries over a concentration range of 150-600 ng/mL ranged from 99.12 to 101.02%, and relative standard deviations ranged from 1.15 to 1.78%.