Ultrafast Analysis of Buprenorphine and Norbuprenorphine in Urine Using the Agilent RapidFire High-Throughput Mass Spectrometry System

Significance of the Topic

Buprenorphine and its metabolite norbuprenorphine are critical analytes in forensic and clinical toxicology for monitoring opioid therapy and detecting abuse. Traditional liquid chromatography mass spectrometry methods often struggle to meet growing demands for higher throughput without sacrificing sensitivity at low nanogram per milliliter ranges.

Study Objectives and Overview

This study evaluates an ultrafast workflow combining enzymatic hydrolysis, automated solid phase extraction, and the Agilent RapidFire high-throughput SPE/MS/MS system. The goal is to achieve rapid cycle times with analytical performance comparable to conventional LC/MS/MS assays over a calibration range of 2.5 to 400 ng/mL.

Methodology

Urine samples spiked with buprenorphine and norbuprenorphine underwent b-glucuronidase hydrolysis at pH 5.0, followed by 96-well Plexa PCX cation exchange SPE. After evaporation and reconstitution, 10 µL of each extract was injected into the RapidFire system. Quantitation employed multiple reaction monitoring with isotopically labeled internal standards and 1/X2 weighted linear regression.

Used Instrumentation

• Agilent RapidFire 360 high-throughput SPE module
• Agilent 6460 Triple Quadrupole Mass Spectrometer
• Agilent MassHunter Qualitative and Quantitative Analysis Software

Main Results and Discussion

Sample cycle time was 15 seconds, corresponding to over 240 analyses per hour. Calibration curves exhibited excellent linearity (R2 > 0.995) across 2.5–400 ng/mL. Limits of quantification were 2.5 ng/mL for both analytes. Intra- and interday accuracy remained within ±10% and precision below 5%. No significant carryover was observed, and isotopic internal standards effectively compensated for matrix effects.

Benefits and Practical Applications

The ultrafast SPE/MS/MS workflow offers high throughput, robust sensitivity, and reproducible quantitation, reducing sample preparation time and instrument idle periods. It is well suited for forensic toxicology, clinical drug monitoring, and high-volume quality control laboratories.

Future Trends and Potential Applications

Integration with automated liquid handling and artificial intelligence-driven data analysis could further streamline workflows. Expanding the platform to other small molecule biomarkers, multiplex panels, and point-of-care testing represents promising directions for rapid drug screening and therapeutic monitoring.

Conclusion

The Agilent RapidFire/MS/MS platform delivers ultrafast, accurate, and precise analysis of buprenorphine and norbuprenorphine in urine, addressing the need for high-throughput toxicology assays without compromise in performance.

References

1. Hegstad S et al. Rapid Quantification of Buprenorphine-Glucuronide and Norbuprenorphine-Glucuronide in Human Urine by LC-MS-MS. Journal of Analytical Toxicology. 2007;31:214–219.
2. Chang Y, Moody DE, McCance-Katz EF. Novel Metabolites of Buprenorphine Detected in Human Liver Microsomes and Human Urine. Drug Metabolism and Disposition. 2006;34:440–448.
3. Agilent Technologies. LC/MS/MS of Buprenorphine and Norbuprenorphine in Whole Blood Using Agilent Bond Elut Plexa PCX and an Agilent Poroshell 120 Column. Publication 5990-9930EN. 2014.
4. Kronsdtand R, Selden TG, Josefsson M. Analysis of Buprenorphine, Norbuprenorphine and Their Glucuronides in Urine by Liquid Chromatography-Mass Spectrometry. Journal of Analytical Toxicology. 2003;27:465–470.