DETERMINATION OF BUPRENORPHINE IN PLASMA BY LIQUID-CHROMATOGRAPHY - APPLICATION TO HEROIN-DEPENDENT SUBJECTS

A rapid, sensitive, precise and accurate HPLC assay with UV detection was developed for the determination of buprenorphine (BN) in human pla sma. This method involved a two-step extraction in the presence of clo thiapine as internal standard. The compounds were chromatographied on a reversed-phase Spherisorb(R) C8 column with a mobile phase consistin g of 0.06 M KH2PO4/Na2HPO4 pH 6.4-acetonitrile-triethylamine-Pic B5(R) (520:480:0.5:15, v/v) and detected at 214 nm. The recovery of BN was greater than 94% with an intra-day relative standard deviation less th an or equal to 4.8% and an inter-day relative standard deviation less than or equal to 14.6% at any studied level. Studies of drug stability during sample storage at -20 degrees C and at +4 degrees C did not sh ow any significative degradation of BN. This method was successfully a pplied to explore the overdose state of heroin-dependent subjects trea ted by high-dose BN. (C) 1998 Elsevier Science B.V. All rights reserve d.