CSC: A Streamlined, Cost-effective Cannabis and Hemp Flower Workflow for Potency Testing

Importance of the Topic

As legalized cannabis markets expand globally, laboratories face mounting pressure to increase sample throughput, reduce per-sample cost, and maintain compliance with evolving regulations. Efficient and reproducible potency testing methods are essential for producers, regulators, and consumers to ensure product safety and consistency.

Study Objectives and Overview

Restek Corporation conducted a comparative study to identify a streamlined, cost-effective workflow for potency testing of cannabis and hemp flower. The investigation evaluated two filtration approaches (FilterMate digestion tubes vs. centrifugation with syringe filtering), two filter pore sizes (0.45 µm and 6 µm), extraction solvent volumes (10 mL vs. 20 mL), and vortex durations (5 min vs. 10 min). Sixteen cannabinoids were quantified by HPLC-UV under isocratic conditions.

Methodology and Instrumentation

Sample preparation steps:

• Weigh 500 mg of ground flower into either FilterMate tubes or 50 mL centrifuge tubes
• Add methanol (10 or 20 mL), vortex for 5 or 10 minutes
• For FilterMate: press plunger to filter; for centrifuge: spin at 4000 rpm and syringe-filter through 0.22 µm
• Dilute filtrate with 25:75 water:acetonitrile and vortex briefly prior to analysis

Analytical instrumentation:

• HPLC column: Raptor ARC-18, 150 × 4.6 mm, 2.7 µm with matching guard
• Mobile phase A: water/5 mM ammonium formate/0.1% formic acid; B: acetonitrile/0.1% formic acid; isocratic 25:75
• Flow rate: 1.5 mL/min; injection volume: 5 µL; detection: UV-Vis at 228 nm; column temperature: 30 °C

Key Results and Discussion

The FilterMate workflow consistently outperformed centrifugation in both cost and time metrics. Eliminating centrifugation reduced per-sample consumable costs by up to 50% and cut sample prep time from over 20 minutes to under 10 minutes. The optimal protocol employed a 6 µm FilterMate tube, 20 mL methanol, and a 10-minute vortex, delivering comprehensive extraction of all 16 cannabinoids with minimal variability.

Benefits and Practical Applications

The proposed workflow provides:

• Significant cost savings on consumables and labor
• Faster turnaround to support high-throughput laboratories
• Reproducible extraction efficiency suitable for QA/QC and regulatory testing
• Ease of implementation using commercially available consumables

Future Trends and Opportunities

Emerging directions include automating the FilterMate process to further boost throughput, coupling with mass spectrometry for enhanced specificity, exploring microextraction to minimize solvent use, and applying data analytics for workflow optimization. Adoption of such innovations can facilitate real-time quality monitoring and decentralized testing models.

Conclusion

Replacing traditional centrifugation with a FilterMate-based approach delivers a streamlined, cost-effective potency testing workflow for cannabis flower. The recommended conditions (6 µm filter, 20 mL solvent, 10 min vortex) achieve reliable cannabinoid extraction, reduce costs, and accelerate laboratory throughput without sacrificing data quality.