Potency Analysis in Hemp and Cannabis Products using a Single-Dilution Combined LC-UV-MS/MS Approach

Importance of the Topic

Reliable quantification of cannabinoids is essential for regulatory compliance, quality control and accurate labeling of cannabis and hemp products. Variations in detector sensitivity and dynamic range pose challenges when measuring both high-abundance cannabinoids like THC and CBD and low-abundance phytochemicals in a single run. A streamlined workflow that combines complementary detection technologies can improve throughput and data consistency across diverse sample types.

Objectives and Study Overview

This study presents a unified single-dilution approach for simultaneous quantitation of 11 key cannabinoids by coupling high-performance liquid chromatography (HPLC) with dual UV and tandem mass spectrometry (MS/MS) detection. The method aims to cover a concentration range from 0.05% to 100% by weight, enabling accurate potency assessment of flower, oils, distillates and concentrates in one 16-minute gradient run.

Methodology and Instrumentation

A homogenized 0.2 g sample was extracted in acetonitrile, sonicated, centrifuged and 1:100 diluted prior to a final 1:5,000 sample dilution. A 2 μL injection was analyzed on an ExionLC AD system fitted with a Phenomenex Luna Omega Polar C18 column (150×4.6 mm, 3 μm) and PDA detector (210–230 nm), coupled to a QTRAP 6500+ triple quadrupole mass spectrometer. The gradient employed 0.1% formic acid in water and 0.1% formic acid in 96% acetonitrile over 16 minutes at 1 mL/min.

Instrumentation

• ExionLC AD HPLC system with PDA (210–230 nm)
• QTRAP 6500+ triple quadrupole MS/MS
• Phenomenex Luna Omega Polar C18, 150×4.6 mm, 3 μm
• SCIEX OS-MQ software for data processing and custom flagging

Main Results and Discussion

The dual-detector workflow provided overlapping calibration ranges: UV detection up to 100% and MS/MS sensitivity down to ~0.005%. Automatic flagging in SCIEX OS-MQ selects the appropriate detector signal and converts concentrations to weight percent using sample mass and dilution factors. Continuous calibration verifications (CCVs) over ~60 injections showed RSDs of 1.6% (MS/MS) and 2.0% (UV). Analysis of 12 cannabis and hemp matrices confirmed accurate quantitation across diverse product types without method adjustments.

Benefits and Practical Applications

• Single sample dilution and injection for 11 cannabinoids reduce preparation time
• Broad dynamic range eliminates the need for multiple dilutions
• Automated software flagging and weight-percent conversion simplify reporting
• Suitable for regulatory potency testing, breeding research and product development

Future Trends and Opportunities

Advances may include integration of ultra-high-pressure LC for faster separations, expanded panels tracking emerging minor cannabinoids and terpenes, and adoption of automated online sample prep for greater throughput. Coupling with data analytics and in-field portable detectors could further streamline compliance testing and cultivar screening.

Conclusion

The combined LC-UV-MS/MS single-dilution method delivers robust, accurate and high-throughput potency analysis for a wide range of cannabis and hemp products. Its unified sample preparation and dual-detector quantitation simplify workflows for laboratories requiring precise measurement of both major and minor cannabinoids.

Reference

Roberts SC, Winkler P, Krepich S, Garber T, Hyland KC, Borton C. Potency Analysis in Hemp and Cannabis Products using a Single-Dilution Combined LC-UV-MS/MS Approach. SCIEX Application Note RUO-MKT-02-9907-A, 2019.