The analysis of hair has been proposed as a tool for monitoring drug-treatment compliance. This study was performed to determine if buprenorphine (BPR) and norbuprenorphine (NBPR) could be detected in human hair after controlled administration of drug and to determine if segmental analysis of hair was an accurate record of the dosing history. Subjects with dark hair (six males, six females) received 8 mg sublingual BPR for a maximum of 180 days. Single hair collections were made once after BPR treatment and stored at -20 degrees C until analysis. Hair was aligned scalp-end to tip and then segmented in 3-cm sections. For this study, it was assumed that the mean hair growth rate was 1.0 cm/month. Deuterated internal standard was added to hair segments (2-20 mg of hair) and digested overnight at room temperature with 1 N NaOH. Specimens were extracted with a liquid-liquid procedure and analyzed by liquid chromatography-tandem mass spectrometry. The limits of quantitation for BPR and NBPR were 3 pg/mg and 5 pg/mg, respectively, for 20 mg of hair. BPR and NBPR concentrations were highest for all subjects in hair segments estimated to correspond to the subject's period of drug treatment. With one exception, NBPR was present in higher concentrations in hair than was the parent compound. BPR concentrations in hair segments ranged from 3.1 pg/mg to 123.8 pg/mg. NBPR concentrations ranged from 4.8 pg/mg to 1517.8 pg/mg. In one subject, BPR and NBPR were not detected in any hair segment. In some subjects, BPR and NBPR were detected in hair segments that did not correspond to the period of drug treatment, suggesting that drug movement may have occurred by diffusion in sweat and other mechanisms. The data from this study also indicate that there is a high degree of intersubject variability in measured concentration of BPR and NBPR in hair segments, even when subjects receive the same dose for an equivalent number of treatment days. Future prospective studies involving controlled drug administration will be necessary to evaluate whether hair can serve as an accurate historical record of variations in the pattern of drug use.

Hair analysis for drugs may be useful for the long-term monitoring of recidivism and treatment compliance. L-alpha-Acetylmethadol, buprenorphine, and methadone are drugs that are used for the treatment of substance abuse. The purpose of this study was to study the relationship between dose, plasma concentration, hair concentration, and hair pigmentation for these compounds and their major metabolites in an animal model. Male Long-Evans rats received either L-alpha-acetylmethadol (1 and 3 mg/kg; n = 6), buprenorphine (1 and 3 mg/kg; n = 5), or methadone (4 and 8 mg/kg; n = 5) by intraperitoneal injection daily for 5 days. Fourteen days after beginning drug administration, newly grown hair was collected and analyzed for either L-alpha-acetylmethadol and two metabolites (L-alpha-acetyl-N-normethadol and L-alpha-acetyl-N,N-dinormethadol), methadone and two metabolites (D,L-2-ethyl-1,5-dimethyl-3,3-diphenylpyrrolinium and D,L-2-ethyl-5-methyl-3,3-diphenyl-1-pyrroline), or buprenorphine and one metabolite (norbuprenorphine). The plasma time course (AUC) for each compound was also determined after a single administration of each drug at the specified doses. There was an approximate dose-dependent increase in measured hair concentration of each parent drug in pigmented hair. The concentrations of L-alpha-acetylmethadol, methadone, and buprenorphine in nonpigmented hair were significantly less than that measured in pigmented hair at either the high or low dose. The metabolites L-alpha-acetyl-N-normethadol and D,L-2-ethyl-1,5dimethyl-3,3-diphenylpyrrolinium were detected at lower concentrations than their respective parent compounds (L-alpha-acetylmethadol or methadone) in pigmented hair. However, the L-alpha-acetyl-N,N-dinormethadol metabolite concentrations in pigmented hair were significantly greater than those of the parent drug after either the low or the high L-alpha-acetylmethadol dose. These data demonstrate that L-alpha-acetylmethadol, methadone, buprenorphine, and metabolites are distributed into hair in a dose-related manner with a preference for pigmented hair.

A sensitive and specific method was developed for the quantitative analysis of l-alpha-acetylmethadol (LAAM), l-alpha-acetyl-N-normethadol (norLAAM), and l-alpha-acetyl-N,N-dinormethadol (dinorLAAM) in hair. In the development of this method, it was determined that sample pretreatment methods performed by the laboratory greatly affect the measured concentrations of drug and metabolite in hair. Deuterated internal standards were added to 20-mg hair samples and the samples digested overnight in a buffered solution of Protease Type VIII enzyme. Digests were extracted by modification of a liquid-liquid extraction procedure developed previously in our laboratory for the analysis of plasma and tissues. Derivatized extracts were analyzed on a Finnigan MAT 4500 mass spectrometer in positive ion chemical ionization mode using methane and ammonia reagent gases, helium carrier gas, and a DB-5MS (30 m, 0.25-micron film thickness) capillary column. The assay was linear to 50 ng/mg hair (r = 0.99) for all three compounds with a limit of quantitation experimentally determined to be 0.5 ng/mg for LAAM and 0.3 ng/mg for norLAAM and dinorLAAM. Intra-assay precision ranged from 1.0 to 10.5% for the three analytes at concentrations of 0.5, 5.0, and 25.0 ng/mg of hair. Interassay precision ranged from 4.7 to 12.9%. The performance of the method was also evaluated for its utility in detecting and quantitating LAAM, norLAAM, and dinorLAAM in hair from rats (n = 6) that had been administered 3 mg/kg LAAM intraperitoneally once daily for five days. LAAM, norLAAM and dinorLAAM were detectable in pigmented hair at concentrations of 1.27 ng/mg (+/-0.04), 1.28 ng/mg (+/-0.014), and 2.89 ng/mg (+/-0.014), respectively. Five laboratory wash solvents were then evaluated for their effect on the measured concentration of LAAM and metabolites in the rat hair. Phosphate buffer and 1% SDS washes substantially reduced the measured LAAM, norLAAM, and dinorLAAM concentrations by at least 30%, which suggests that drug incorporated into hair is removed (extracted) during the laboratory wash procedures. Wash procedures using methanol, methylene chloride, or water reduced the measured concentrations by no more than 20%. Because measured concentrations of LAAM, norLAAM, and dinorLAAM in hair appear to depend on the specific wash procedures used by a laboratory, quantitative data must be interpreted cautiously based on the sample pretreatment conditions.