Terpenes in Hemp and Cannabis Determined Using EI GC-MS/MS

Importance of the Topic

Terpenes form the aromatic fingerprint of hemp and cannabis and influence consumer experience and physiological effects. Accurate terpene profiling supports quality control of raw materials and finished products.

Objectives and Study Overview

This study demonstrates a unified method using EI GC-MS/MS to analyze ten terpene compounds in one hemp and one cannabis cultivar. The same system also performs trace pesticide analysis, maximizing lab efficiency and reducing instrument footprint.

Methodology and Instrumentation

• Sample preparation 100 mg ground plant material extracted with 5 mL ethyl acetate containing n-tridecane internal standard, followed by sonication, centrifugation, and transfer to autosampler vials
• Gas chromatography Agilent 7890B with 7693A autosampler, Restek Rxi-5MS column (20 m×0.18 mm×0.18 µm), helium at 0.4 mL/min, injection 1 µL split 50 ∶ 1 at 275 °C, temperature program 40 °C hold then ramp to 320 °C for an 11 min run
• Mass spectrometry Waters Xevo TQ-GC, EI 70 eV, 200 µA, source 175 °C, transfer line 275 °C, optimized MRM transitions for ten terpenes, concurrent RADAR full scan for qualitative monitoring
• Data processing MassLynx v4.2 with TargetLynx XS and NIST 2017 library for spectrum matching

Key Results and Discussion

• Optimized carrier gas linear velocity (29 cm/s at 40 °C) and temperature ramps achieved baseline separation of critical terpene pairs with peak widths under 3 s and ~50 data points per peak
• RADAR acquisition identified co-extracted cannabidiol and informed final bake-out time to prevent carryover
• Quantitation yielded total terpene content of 0.0122 wt% in hemp and 0.0384 wt% in cannabis cultivar Mendo Purps
• Recovery in hemp ranged from 84 – 105% (terpinolene at 64%) and in cannabis from 99 – 126% (terpinolene at 73%)
• Multiple MRM transitions and ion ratio confirmation provided high specificity and adaptability for future analyte expansion

Benefits and Practical Applications

This combined method enables terpene profiling and pesticide residue testing on a single platform, improving throughput, reducing operator training, and supporting quality assurance of cultivars and derived products.

Future Trends and Potential Applications

• Expansion to additional terpene isomers and minor terpenoids in complex matrices
• Integration with alternative detectors or ambient ionization for rapid screening
• Automation of sample preparation and data analysis to increase throughput
• Use of MRM ratio metrics as a robust confirmation tool in regulated environments

Conclusion

This application note demonstrates that EI GC-MS/MS with optimized sample preparation and RADAR acquisition provides a rapid, robust, and accurate method for profiling terpenes in hemp and cannabis. The dual use for pesticide and terpene analysis maximizes laboratory resource utilization.

References

1. Pichersky E and Raguso RA Why do plants produce so many terpenoid compounds New Phytologist 2018 220 692–702
2. Lange BM Evolution of plant secretory structures and emergence of terpenoid diversity Annual Review of Plant Biology 2015 66
3. Booth JK and Bohlmann J Terpenes in Cannabis sativa from plant genome to humans Plant Science 2019
4. Russo EB Taming THC potential cannabis synergy and phytocannabinoid terpenoid entourage effects British Journal of Pharmacology 2011 163 1344–1364
5. Waters Corporation Analysis of residual pesticides and mycotoxins in cannabis using UPLC-MS/MS and GC-MS/MS Application Note 720006465en 2018
6. Ibrahim EA et al Analysis of terpenes in Cannabis sativa L using GC/MS method development validation and application Planta Medica 2019 431–438
7. de Zeeuw J Impact of GC parameters on separation Part 2 choice of column internal diameter Restek Corporation