Extraction and GC/MS Analysis of Cannabinoids from Brownies using roQ™ QuEChERS Extraction Salts and a Zebron™ ZB-5MSPLUS ™ GC Column

Significance of the topic

The reliable quantification of cannabinoids in edible products such as brownies is essential for quality control, regulatory compliance, and consumer safety. Complex food matrices pose challenges due to fats, sugars and other interferents, making efficient sample cleanup crucial for accurate results.

Objectives and overview

This study aims to develop and validate a streamlined extraction and GC/MS method for the simultaneous analysis of cannabidiol, delta-9-tetrahydrocannabinol and cannabinol in chocolate brownies. The approach integrates an optimized QuEChERS extraction protocol with a deactivated GC column to ensure sharp chromatographic peaks and minimal matrix effects.

Methodology and Instrumentation

Extraction Procedure

1. Combine 1 g of brownie with 10 mL water in a 50 mL centrifuge tube.
2. Shake until dissolved using a mechanical shaker.
3. Add roQ QuEChERS EN15662 salt packet and 10 mL acetonitrile.
4. Shake for 3 minutes, then centrifuge at 2700 rpm for 5 minutes.
5. Transfer 1 mL of supernatant to an autosampler vial for GC/MS.

Analytical Instrumentation

• GC Column: Zebron ZB-5MSPLUS, 30 m x 0.25 mm x 0.25 µm
• Carrier Gas: Helium at 1.5 mL/min (constant flow)
• Injection: Splitless, 1 µL at 250 °C
• Oven Program: 100 °C (1 min) to 320 °C at 50 °C/min, hold 2 min
• Detection: Single quadrupole MS at 320 °C

Results and Discussion

The method achieved baseline separation and excellent peak symmetry for all three cannabinoids at a spiked level of 1 µg/g. Total ion chromatograms demonstrated minimal background interference from the brownie matrix, confirming the efficiency of the roQ QuEChERS cleanup. Reproducibility was high, with retention time RSDs below 1% and acceptable signal-to-noise ratios.

Benefits and practical applications

• Rapid sample preparation suitable for high-throughput testing.
• Effective removal of fats and pigments enhances MS performance.
• Applicable to a range of edible matrices in compliance and research laboratories.

Future trends and potential uses

Advancements may include coupling QuEChERS with tandem MS for lower detection limits, automation of sample handling, and extension to a broader panel of cannabinoids and metabolites in complex foods.

Conclusion

The combination of roQ QuEChERS extraction and a deactivated Zebron ZB-5MSPLUS GC column delivers a robust, efficient workflow for cannabinoid analysis in brownies. This protocol ensures precise quantitation, streamlined cleanup, and adaptability for routine analytical laboratories.