High-sensitivity analysis of buprenorphine, norbuprenorphine, buprenorphine glucuronide, and norbuprenorphine glucuronide in plasma and urine by liquid chromatography–mass spectrometry

Abstract

A new method using ultra-fast liquid chromatography and tandem mass spectrometry (UFLC–MS/MS) was developed for the simultaneous determination of buprenorphine and the metabolites norbuprenorphine, buprenorphine-3β-glucuronide, and norbuprenorphine-3β-glucuronide in plasma and urine. Sample handling, sample preparation and solid-phase extraction procedures were optimized for maximum analyte recovery. All four analytes of interest were quantified by positive ion electrospray ionization tandem mass spectrometry after solid-phase microextraction. The lower limits of quantification in plasma were 1 pg/mL for buprenorphine and buprenorphine glucuronide, and 10 pg/mL for norbuprenorphine and norbuprenorphine glucuronide. The lower limits of quantitation in urine were 10 pg/mL for buprenorphine, norbuprenorphine and their glucuronides. Overall extraction recoveries ranged from 68–100% in both matrices. Interassay precision and accuracy was within 10% for all four analytes in plasma and within 15% in urine. The method was applicable to pharmacokinetic studies of low-dose buprenorphine.

Buprenorphine and nor‐buprenorphine levels in head hair samples from former heroin users under Suboxone® treatment

“…It is metabolized in the liver by N‐deakylation, via CYP3A4, CYP2C9, and CYP2C8 of cytochrome P450, primarily to NBUP. It is also metabolized by glucuronidation, which is catalyzed by UDP‐glucuronosyl transferases (UGT), to buprenorphine‐3‐glucuronide and norbuprenorphine‐3‐glucuronide respectively . The metabolites of BUP are pharmacologically active in animals.…”

Current trends in environmental analysis of human metabolite conjugates of pharmaceuticals

“…The latter step is critical in minimising ion suppression or enhancement common in electrospray ionisation. An alternative was use of SPE micro-extraction plates [24] with MCX sorbent, which supports an affinity for bases and is stable in organic solvents. The main advantage of micro-extraction plates compared to cartridges (e.g., Oasis HLB) is the small amount of eluent necessary for conditioning of the plates (ca.…”

“…Morphine glucuronides at environmentally-applicable concentrations were quantified using MCX microextraction well plates for extraction, followed by HPLC separation with a Kinetix core-shell column using an gradient elution with 0.1% aqueous formic acid and acetonitrile [24]. Values for LOD of 1-10 ng/L, 68-98% recoveries, and a linear dynamic range of 20-1 Â10 5 ng/L were reported ( Table 2).…”

“…For a qualitative comparison to the above study [24], various benzodiazepine glucuronides (i.e., oxazepam and temazepam) were extracted from whole blood using HLB micro-extraction well plates, and separated using a C18 column with a water and acetonitrile with 2 mM ammonium formate buffer and 0.1% formic acid eluent mixture [21]. This resulted in much worse LOD values of 250 ng/L, poorer recoveries of 36-51%, and a high range of 500-1 Â10 6 ng/L.…”

“…Thus, the trade-off in increased recovery and quantification for conjugates could also limit the effectiveness of analyzing the parent compounds. Also, as mentioned above, it is possible that the core-shell technology of the Kinetex column used by Regina et al [24] could have resulted in smaller plate heights and shorter diffusion distances due to the smaller pore size on the surface of the sorbent particles. This could allow more uniform elution and increased resolution due to less peak broadening, or tailing.…”