Differentiating Cannabis and Hemp with the Cannabis Analyzer for Potency

Importance of the Topic

Since the 2018 legalization of hemp under U.S. federal law, cannabidiol (CBD) products have surged in both medical and commercial markets. Differentiating hemp from cannabis relies on accurate measurement of psychoactive cannabinoids, particularly Δ9-tetrahydrocannabinol (Δ9-THC), against regulatory thresholds. Reliable, sensitive analytical methods ensure compliance, public safety and support therapeutic product development.

Objectives and Overview of the Study

This study aimed to establish a straightforward, rugged high-performance liquid chromatography (HPLC) method coupled with ultraviolet detection for quantifying four key cannabinoids (CBD, Δ9-THC, Δ8-THC and THCA). The method enables clear differentiation between hemp (≤0.3% total THC) and cannabis samples and supports quality control in industrial and research laboratories.

Methodology

A six-point calibration (0.5–100 mg/L) and two quality control levels (2.5 and 25 mg/L) were prepared in triplicate. Linear regression evaluation yielded correlation coefficients (R2) ≥ 0.999 for all analytes. Key methodological features include:

• Gradient separation on a protected NexLeaf CBX column (150 × 4.6 mm, 2.7 μm) at 35 °C.
• Mobile phases: 0.085% phosphoric acid in water (A) and in acetonitrile (B) with a gradient from 70% to 95% B.
• Flow rate of 1.6 mL/min and 5 μL injection volume.
• Detection at 220 nm using a built-in UV detector.

Used Instrumentation

• Shimadzu Cannabis Analyzer for Potency™ HPLC system with integrated UV-Vis detector.
• NexLeaf CBX guard column cartridge and guard holder.
• Phytocannabinoid Mixture 4 certified reference materials in acetonitrile.

Main Results and Discussion

Calibration curves for all four cannabinoids demonstrated excellent linearity (R2 ≥ 0.9997) and repeatability (relative standard deviation < 6%). Potency determinations included:

• A commercial CBD tincture measured at 67.47 mg/mL (label claim: 50 mg/mL), demonstrating method accuracy.
• A dry CBD hemp sample containing 92.1% CBD and negligible Δ9-THC, confirming hemp classification.
• A flower-hemp sample with 4.52% CBD and 8.24% total THC, exceeding the 0.3% threshold and thus classified as cannabis.

Chromatograms showed clear resolution and consistent retention times for all analytes, underpinning robust sample differentiation.

Benefits and Practical Applications of the Method

By combining simple sample preparation with a fast gradient and integrated detection, the method provides:

• High sensitivity and accuracy for regulatory compliance.
• Rapid throughput suitable for QA/QC laboratories.
• Cost-effective operation without the need for mass spectrometry.

Future Trends and Opportunities

Advances may include:

• Extension to minor cannabinoids and terpene profiles to support broader product characterization.
• Integration with mass spectrometry for confirmatory analysis and improved selectivity.
• Automation of sample handling to increase throughput in large testing facilities.
• On-site or portable versions of the analyzer for field compliance testing.

Conclusion

The presented HPLC-UV method on the Shimadzu Cannabis Analyzer for Potency™ offers a reliable, user-friendly approach to quantify major cannabinoids and distinguish hemp from cannabis samples. Its precision, accuracy and simplicity make it well suited for industrial, regulatory and research laboratories engaged in cannabinoid analysis.

References

No references were provided in the original document.