Analysis of Cannabinoids and Their Metabolites in Urine Using the MassHunter StreamSelect LC/MS System

Importance of the Topic

A rapid and selective analysis of cannabinoids and their metabolites is crucial in clinical research, forensic testing, and therapeutic monitoring. High-throughput screening ensures timely results for large sample sets while maintaining analytical specificity and sensitivity.

Objectives and Study Overview

The study aimed to develop a six-minute LC/MS/MS method for six cannabinoids (CBD, CBDA, CBN, THC, THC-COOH, THC-OH) in urine. A key goal was to enhance throughput by employing four simultaneous, staggered chromatographic streams controlled by MassHunter StreamSelect software.

Methodology and Instrumentation

The analytical workflow involved spiking blank urine with labeled and unlabeled standards to create calibrators (5–5,000 ng/mL) and quality samples (100 and 200 ng/mL). Samples were prepared by simple dilution in 70% methanol containing deuterated internal standards.

• Liquid Chromatography: Four Agilent 1290 Infinity II UHPLC streams, Poroshell 120 EC-C18 column (2.1×50 mm, 2.7 µm), 0.4 mL/min flow, 6-minute gradient at 50 °C.
• Mass Spectrometry: Agilent 6470 triple quadrupole with Jet Stream ESI+, MRM transitions for each analyte and its deuterated analogue, optimized fragmentor, collision energy, and cell acceleration voltage.
• Software: MassHunter StreamSelect for shared-stream, independent calibration acquisition; MassHunter Quantitative Analysis with 1/x weighting for curve fitting.

Main Results and Discussion

StreamSelect acquired 894 samples in 24 hours (97 seconds/sample), a 3.7× throughput increase over the 6-minute single-stream method. Retention time reproducibility across 1,000 injections showed RSDs of 0.43–1.54%. Individual calibration curves for all analytes displayed linearity with R²>0.996; combined curves had R² between 0.993 and 0.997. Quantitation of 200 ng/mL samples yielded accuracy of 95.3–109.1% and RSDs of 0.47–2.79% across streams, confirming equivalent performance and robustness.

Benefits and Practical Application of the Method

The four-stream StreamSelect approach delivers reliable, high-throughput quantitation ideal for clinical laboratories, forensic toxicology, doping control, and industrial quality testing. It minimizes run time without sacrificing accuracy or precision, making it suitable for large-scale studies.

Future Trends and Potential Applications

Advancements may include integration with high-resolution mass spectrometry for broader untargeted screening, further automation of sample preparation, expansion to other biological matrices, and development of miniaturized portable LC/MS platforms for point-of-care testing.

Conclusion

A robust LC/MS/MS method for six urinary cannabinoids was established using Agilent’s StreamSelect four-stream platform. The approach significantly increases sample throughput while maintaining high analytical performance and reproducibility.

References

• Szczesniewski A, McCann K. Analysis of Cannabinoids and Their Metabolites in Urine Using the MassHunter StreamSelect LC/MS System. Agilent Technologies Application Note. 2019.