TOF Cannabis Webinar

Significance of the Topic

Accurate quantification and quality control of cannabinoids in hemp products is essential for regulatory compliance, consumer safety and consistent product performance. Modern analytical workflows combine high-resolution liquid chromatography with precise mass spectrometry to separate and unambiguously identify individual cannabinoids across a wide concentration range. In addition, simultaneous screening for pesticides and other contaminants in cannabis matrices supports comprehensive safety testing in laboratories operating under legal frameworks.

Objectives and Study Overview

The primary aim was to develop a rapid UHPLC–TOF method that can reliably quantify high levels of CBD and CBDA alongside trace levels of THC in a single 6-minute run. Secondary goals included demonstrating high mass accuracy and resolution for confident peak annotation and extending the workflow to untargeted screening of pesticides and toxicological analytes using an All Ions MS/MS approach.

Methodology and Instrumentation

• Chromatography: Agilent 1290 Infinity II UHPLC system with quaternary pump, multisampler and column thermostat.
• Column: Zorbax Bonus-RP polar-linked alkyl phase (2.1×50 mm, 1.8 µm), 50 °C; flow rate 0.5 mL/min.
• Mobile Phases: A) Water; B) Methanol; C) 0.1% formic acid with ammonium formate buffer.
• Gradient: 0–5 min, %B increased from 72% to 95%, %C held at 5%.
• Detection: UV at 254 nm and accurate-mass TOF or Q-TOF MS operating at 6100–14 000 FWHM resolution, mass accuracy better than 3 ppm.
• Fragmentation: All Ions MS/MS using alternating low/high collision energies and PCDL libraries for precursor–fragment correlation.

Main Results and Discussion

• Chromatographic separation of ten cannabinoids (CBDV, THCV, CBC, CBG, CBN, CBDA, Δ9-THCA, CBGA, CBD, THC) in a 5 min injection demonstrated resolution and peak shape consistency.
• LOQ for THC was established at 12.5 ppb, while CBD quantitation spanned up to 5000 ppm with linear calibration (R2 > 0.995).
• Mass resolution of 6 100–14 000 FWHM enabled baseline separation of isobaric compounds, with mass errors below 1 ppm in many cases.
• Replicate analyses of a 25 ppm standard over 20 injections showed retention time RSD < 1% and area reproducibility within 4% RSD, confirming method precision and low carryover.
• All Ions MS/MS workflows extracted precursor and fragment ion chromatograms for library matching, yielding high co-elution scores and added confirmation power in complex matrices.
• Pesticide screening using a QuEChERS extract of CBD oil detected targeted pesticide residues from a predefined PCDL subset in a single run. A panel of 96 drugs of abuse spiked into hemp oil matrix was also quantified with correlation coefficients of 0.995–0.999.

Benefits and Practical Applications

• Single-run quantitation of multiple cannabinoids over a broad dynamic range accelerates potency testing in QA/QC labs.
• High mass accuracy and resolution reduce false positives and enhance confidence in analyte identification, even for isobaric interferences.
• All Ions MS/MS provides untargeted screening capability for contaminants such as pesticides and controlled substances without additional sample preparation or injection time.
• Compact 6 min method and minimal solvent usage improve laboratory throughput and sustainability.

Future Trends and Potential Applications

Innovations in high-throughput accurate-mass analysis will focus on expanding spectral libraries for emerging cannabinoids, pesticides and novel psychoactive substances. Integration of artificial intelligence for automated peak annotation and real-time process monitoring could further streamline regulatory compliance. Miniaturized or benchtop accurate-mass instruments may extend these capabilities to on-site testing and field deployment.

Conclusion

The presented UHPLC–TOF workflow offers a robust, high-speed solution for simultaneous quantitation of major and minor cannabinoids, coupled with comprehensive contaminant screening. Its excellent mass accuracy, resolution and All Ions MS/MS confirmation deliver reliable results for cannabis quality control and safety testing in accordance with regulatory requirements.

References

1. D’Antonio S. Application of UHPLC–TOF for Cannabis Potency and Safety Analysis, Agilent Technologies Application Note, 2016.
2. Herb.co, Top 10 Cannabinoids, 2016.