Spectral Fidelity of Terpenes in Cannabis with Hydrogen Carrier Gas

Importance of the Topic

Terpenes in cannabis contribute to strain specific aroma and flavor and serve as key quality control markers. Reliable profiling of these compounds supports product characterization, regulatory compliance and consumer safety. Given global helium shortages and rising costs, exploring hydrogen as a carrier gas is critical for sustainable GC MS operations.

Objectives and Study Overview

This study examines the spectral fidelity of 21 common cannabis terpenes using a single quadrupole GC MS in selective ion monitoring mode with hydrogen carrier gas. Results are compared against standard helium methods and NIST 23 library spectra to assess identification confidence.

Used Instrumentation

• Agilent single quadrupole GC MS with HydroInert source
• Helium and hydrogen carrier gas configurations following Agilent method guides
• MassHunter Unknowns Analysis software version 10.2 for spectral deconvolution and library matching

Methodology

Standard mixes containing 21 terpenes were prepared per Agilent protocols. Samples were analyzed in both scan and SIM modes with helium and hydrogen carrier gases. The HydroInert source minimized redox reactions in the MS ion source. Collected spectra were deconvoluted and matched against the NIST 23 library using default MassHunter settings.

Results and Discussion

Library match scores for hydrogen generated spectra ranged from 79.7 to 98.8 percent against NIST 23. Menthol was an outlier with similar low scores in both gases. Excluding menthol, hydrogen match scores spanned 90.7 to 98.8 percent, closely matching helium results. Overlay comparisons for D limonene, menthol and cedrol confirmed conserved ion distribution and high spectral fidelity under hydrogen conditions.

Benefits and Practical Applications

Employing hydrogen with the HydroInert source preserves spectral fidelity, enabling direct transfer of established quantification and qualifier ions from helium methods. This approach reduces reliance on helium, lowers operational costs and supports robust terpene profiling in cannabis testing laboratories.

Future Trends and Potential Applications

Integration of advanced automation and high throughput sample preparation will enhance terpene analysis workflows. Expanded hydrogen compatible ion sources and dedicated spectral libraries for hydrogen conditions will further improve identification accuracy. Broader application to other volatile compound classes is anticipated.

Conclusion

The results demonstrate that hydrogen carrier gas combined with an inert MS source is a viable alternative for accurate terpene analysis in cannabis. Conserved spectral fidelity ensures reliable library matching and facilitates the transition away from helium in GC MS operations.

References

1. Haddad SP Patel SU Westland JL Analysis of Terpenes in Cannabis with Hydrogen Carrier Gas and the Agilent HydroInert Source on the Agilent Intuvo 9000 5977C GC MS Agilent Technologies application note 5994-6216EN 2023
2. Haddad SP Patel SU Westland JL Analysis of Terpenes in Cannabis with Hydrogen Carrier Gas and the Agilent HydroInert Source on the Agilent 8890 5977C GC MS Agilent Technologies application note 5994-6511EN 2023
3. Agilent Inert Plus GC MS System with HydroInert Source Agilent Technologies technical overview 5994-4889EN 2022
4. Agilent EI GC MS Instrument Helium to Hydrogen Carrier Gas Conversion Agilent Technologies user guide 5994-2312EN 2022
5. Agilent GC MS Hydrogen Safety Agilent Technologies user guide G7006-90053 2022
6. Hydrogen Safety for the Agilent Intuvo GC System Agilent Technologies technical overview 5994-5412EN 2022
7. Hydrogen Safety for the Agilent 8890 GC System Agilent Technologies technical overview 5994-5413EN 2022
8. Hollis JS Harper T Macherone A Terpenes Analysis in Cannabis Products by Liquid Injection using the Agilent Intuvo 9000 5977B GC MS System Agilent Technologies application note 5994-2032EN 2020
9. Patel SU Westland JL Haddad SP Fully Automated Sample Preparation for the Analysis of Terpenes in Cannabis Flower Agilent Technologies application note 5994-6007EN 2023