Jack Cochran, Lindsey Shear-Laude, Alex Hodgson VUV Analytics Emerald Conference. #emeraldconference

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1 Better Living Through (Sensory) Chemistry: Gas Chromatography - Vacuum Ultraviolet Spectroscopy as a New Tool for Analysis of Terpenes and Residual Solvents in Cannabis Products Jack Cochran, Lindsey Shear-Laude, Alex Hodgson VUV Analytics 2018 Emerald Conference #emeraldconference

2 Acknowledgments Amanda Rigdon, Ken Snoke, Wes Burk, Cliff Beneventi, and others! Emerald Scientific Julie Kowalski Trace Analytics 2018 Emerald Conference #emeraldconference

3 Jack s flight details for The Emerald Conference

4 Presentation Outline Introduction to vacuum ultraviolet spectroscopy and VGA-100 Analysis of residual solvents and terpenes with GC-VUV Possibility of combined solvents and terpenes analysis

5 Vacuum Ultraviolet Detector for GC Absorbance spectrometer 120 to 240 nm ( everything absorbs in the 120 to 200 nm range) Detects things that are problematic for other detectors Formaldehyde, formic acid, water, carbon dioxide, carbon monoxide, etc. Good detectability Low tens to low hundreds pg depending on compound Qualitative and quantitative analysis Absorbance spectral library and Beer-Lambert Law (A c) Separation of coeluting analytes, including isomers Spectral filters and spectral deconvolution

6 Gas Chromatograph VUV Analytics VGA to 240nm 1 to 90 spectra/sec ~ 75 cm Deuterium Lamp CCD Detector ~43 cm Absorbance Spectrum ~33 cm

7 Gas Chromatograph VUV Analytics VGA to 240nm 1 to 90 spectra/sec ~ 75 cm Deuterium Lamp CCD Detector ~43 cm Absorbance Spectrum ~33 cm

8 VUV Absorbance Spectra (125 to 240 nm) Acetone Benzene Butane Dichloromethane

9 VUV Absorbance Spectra 125 to 240 nm Propane Butane Pentane Hexane

10 Sample fails quality assurance testing if results exceed table limits Residual solvent results of more than 5000 ppm for class three solvents, 50 ppm for class two solvents, and 2 ppm for class one solvents fail Certified labs must test for the solvents in table at a minimum

11 Animal carcinogens and other possible toxic effects PDE is Permissible Daily Exposure FDA 2012 companion document for the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use And more

12 Headspace Transfer Line Flame Ionization Detector The job of the static headspace instrument is to get solvent (red circles) into gas phase for transfer to GC column. Static Headspace Autosampler GC Column Gas Chromatograph

13 Slow equilibration times. GC run time of 60 min.

14 Static Headspace Conditions for GC-VUV Gerstel MPS2 Syringe temperature: 90 C Incubation temperature: 80 C Incubation time: 10 min Agitator: 250 rpm 10 sec on, 1 sec off Injection volume: 250 µl Injection speed: 200 µl/sec Heating and shaking Sampling and injection

15 Headspace phase Sample phase Solvents Original sample + Equilibrated sample Water and Excipient

16 GC-VUV for Residual Solvents Agilent 6890 GC 2mm ID Topaz straight inlet liner, 250 C, split ratio m x 0.25mm x 1.40µm Rxi-624Sil MS He 4 ml/min constant flow 35 C (1 min), 30 C/min to 245 C VUV Analytics VGA-100 Transfer line and flow cell 275 C Nitrogen makeup gas ~0.36 psi Acquisition range 125 to 240 nm Acquisition rate 4.5 spectra/sec Run time 8 min

17 Oxygen Water Cyclohexane Static Headspace GC-VUV Class 2 Residual Solvents, USP Limit 100 mg Citric Acid, 2 ml Water m- and p-xylenes Methylcyclohexane Toluene nm cis-1,2-dichloroethene Dichloromethane Methanol o-xylene Cumene Tetralin 8 min

18 Dichloromethane R 2 = x USP Limit Class 2 Residual Solvents 100 mg Citric Acid 2 ml Water 0.1x 02.5x 0.5x Static Headspace GC-VUV 18

19 Class 2 Residual Solvents 100 mg Citric Acid 2 ml Water Chlorobenzene Ethylbenzene m- and p-xylenes 2 x USP Limit USP Limit 0.5 x USP Limit 0.25 x USP Limit 0.10 x USP Limit Blank o-xylene

20 1,1,1-Trichloroethane Class 1 Residual Solvents Static Headspace GC-VUV Carbon tetrachloride nm nm nm nm 3.19 min Benzene 1,2-Dichloroethane

21 Vacuum Ultraviolet Absorbance Spectra 1,2-Dichloroethane Benzene <<< 120 to 170 nm >>> <<< 170 to 240 nm >>>

22 Class 1 Residual Solvents Static Headspace GC-VUV Spectral Filter nm (full absorbance range) nm (aromatic absorbance range) 1,1,1-Trichloroethane Benzene Carbon tetrachloride 3.19 min 1,2-Dichloroethane

23 1,1,1-Trichloroethane 1,2-Dichloroethane < > Benzene nm nm nm <---> <-> Carbon tetrachloride No good spectral filter for 1,2-dichloroethane? 1,2-Dichloroethane Benzene

24 Benzene VUV spectral deconvolution results in pure chromatographic peaks 1,2-Dichloroethane

25 Samples Analyzed Throat sprays Phenol anesthetic Kids medicine Acetominophen Herbal Allergy relief Claritin Immune support tablet Similar to Airborne Hangover relief NSAID and caffeine

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28 Hangover Drug Facts - Uses For temporary relief of minor aches and pains associated with a hangover Helps restore mental alertness or wakefulness when experiencing fatigue or drowsiness associated with a hangover Also for temporary relief of headaches or body aches and pains alone

29 Hangover Drug Facts - Ingredients Choline salicylate (NSAID) Pain reliever Caffeine Pain reliever aid Citric acid, sodium citrate, sodium benzoate Natural flavors, purified water Sucralose (sweetener) Anything else?

30 Oxygen Water Static Headspace GC-VUV?

31 Oxygen Water Static Headspace GC-VUV Ethanol

32 Sample spectrum (from Hangover) Library spectrum (ethanol)

33 ~ mg concentrate in a headspace vial Full evaporation technique mitigates matrix effects Makes quantification easier (more accurate?) Shatter

34 Water Acetone Ethanol iso-pentane Butane iso-butane 2-Methylpentane 3-Methylpentane Hexane Benzene Heptane Toluene Ethylbenzene m-xylene p-xylene o-xylene

35 β-myrcene β-pinene Limonene β-caryophyllene α-pinene Terpinolene Linalool α-humulene Ocimene Caryophyllene oxide

36 β-myrcene 5 µl steam-distilled cannabis flower extract and 2 µl gasoline FET static headspace GC-VUV 20 min equilibration time 17 min GC time β-pinene Limonene β-caryophyllene Butane α-pinene α-humulene Hexane Heptane Toluene m-xylene p-xylene Linalool

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38 Monoterpenes and Monoterpenoids Sesquiterpenes and Sesquiterpenoids α-pinene β-pinene Eucalyptol β-caryophyllene α-humulene p-cymene Linalool Flavor, fragrance, medicine, entourage effect for cannabis (-)-Guaiol

39 Detector Response Static Headspace GC-VUV of Cannabis Terpenes Standard nm nm α-pinene 12. Terpinolene 2. Camphene 13. Linalool 3. β-myrcene 14. Isopulegol 4. β-pinene 15. Geraniol 5. 3-Carene 16. β-caryophyllene 6. α-terpinene 17. α-humulene 7. cis-ocimene 18. cis-nerolidol 8. Limonene 19. trans-nerolidol 9. p-cymene 20. Guaiol 10. trans-ocimene 21. α-bisabolol 11. γ-terpinene Last analyte elutes before 9 min! Time (min)

40 Monoterpene t R min Formula MW Sources α-pinene 3.87 C 10 H Coniferous trees, rosemary, eucalyptus Camphene 4.03 C 10 H Camphor, neroli, valerian β-myrcene 4.21 C 10 H Thyme, cardamom, hops, cannabis β-pinene 4.25 C 10 H Nutmeg, rosemary, sage Δ-3-Carene 4.43 C 10 H Turpentine, rosemary, cedar α-terpinene 4.50 C 10 H Allspice, juniper, marjoram cis-ocimene 4.53 C 10 H Basil, lavender, clary sage Limonene 4.58 C 10 H Citrus fruits, mint trans-ocimene 4.64 C 10 H Basil, lavender, clary sage γ-terpinene 4.77 C 10 H Citrus fruits, cumin, Syrian oregano Terpinolene 4.98 C 10 H Allspice, citrus fruits, juniper

41 Electron ionization mass spectra of coeluting terpene isomers β-myrcene β-pinene

42 Normalized Absorbance VUV Absorbance Spectra of Monoterpene Isomers α-pinene β-pinene β-myrcene Limonene cis-ocimene trans-ocimene Wavelength (nm)

43 Detector Response Spectral Deconvolution of Coeluting Peaks nm Limonene α-terpinene p-cymene cis-ocimene trans-ocimene Summary: XXX XXX XXX Time (min)

44 Absorbance Region 1 Single Analyte Spectral Matching α-terpinene Summed Retention Region Spectrum Summed Target Spectrum Best Fit; R^2 = alpha-terpinene Wavelength (nm)

45 Absorbance Region 2 Summation of Spectra from Coelution # Summed Retention Region Spectrum Summed Target Spectra Best Fit; R^2 = alpha-terpinene cis-ocimene α-terpinene cis-ocimene Wavelength (nm)

46 Absorbance Region 3 Summation of Spectra from Coelution # Summed Retention Region Spectrum Summed Target Spectra Best Fit; R^2 = Limonene p-cymene Limonene p-cymene Wavelength (nm)

47 Absorbance Region 4 Single Analyte Spectral Matching trans-ocimene Summed Retention Region Spectrum Summed Target Spectrum Best Fit; R^2 = trans-ocimene Wavelength (nm)

48 Peak Area Peak Area Peak Area Peak Area Static Headspace GC-VUV Linearity of Terpenes α-pinene Limonene y = x R² = y = 0.046x R² = Concentration (ppm) Linalool y = x R² = to 500 ppm Concentration (ppm) α-humulene y = x R² = Concentration (ppm) Concentration (ppm)

49 *non-target Eucalyptus Essential Oils α-pinene 2. Limonene 3. Eucalyptol* Lavender cis-ocimene 2. trans-ocimene 3. Linalool Neroli 1. β-pinene 2. Limonene 3. Linalool Peppermint Limonene 2. Eucalyptol* 3. Menthol 1* 4. Menthol 2* Sweet Orange Tea Tree 1. Limonene 2 1. α-pinene α-terpinene 3. γ-terpinene Summary: XXX XXX XXX

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51 Analysis of Steam-Distilled Cannabis Extracts Agilent 6890 GC 4mm Precision split liner with wool, 250 C, 1 µl, split ratio 10 or m x 0.25mm x 0.25µm Rxi-1301Sil MS Run time 12.6 min He 2 ml/min constant flow 40 C (0.1 min), 16 C/min to 240 C VUV Analytics VGA-100 Transfer line and flow cell 275 C Nitrogen makeup gas 0.25 psi Acquisition range 125 to 240 nm Acquisition rate 5 spectra/sec

52 β-myrcene Limonene Sample 7 Steam-Distilled Cannabis Extracts GC-VUV β-pinene α-pinene Linalool β-caryophyllene α-humulene Caryophyllene oxide Sample 17 Terpinolene Fenchol Sample 15

53 Terpenes (mg/ml) in Steam-Distilled Extracts of Cannabis (GC-VUV) Terpene α-pinene β-pinene β-myrcene Limonene cis-ocimene trans-ocimene Terpinolene Linalool Fenchol β-caryophyllene α-humulene Caryophyllene oxide

54 Sample 5 Steam-Distilled Cannabis Extracts GC-VUV β-myrcene Limonene β-pinene α-pinene Linalool Fenchol β-caryophyllene α-humulene Caryophyllene oxide Sample 16

55 Overlay of 17 Steam-Distilled Cannabis Extracts Detector Response min 4.5 5, trans-ocimene 13. γ-terpinene 14. Terpinolene 15. Fenchone 16. Linalool 17. Fenchol 18. Isopulegol 19. Camphor 20. Isoborneol 21. Menthol 22. Borneol 1. α-pinene 2. Camphene 3. β-pinene 4. β-myrcene 5. α-phellandrene 6. 3-Carene 7. α-terpinene 8. Limonene 9. cis-ocimene 10. p-cymene 11. Eucalyptol , Time (min) 30, , Citronellol 24. Nerol 25. cis-citral 26. Thymol 27. β-caryophyllene 28. α-humulene 29. trans-nerolidol 30. Caryophyllene oxide 31. Guaiol 32. α-bisabolol min

56 Summary GC-VUV is a new tool for analysis of residual solvents and terpenes in cannabis samples Absorbance spectrum provides authoritative identification VUV absorbance spectra deconvolution promotes accurate qualitative and quantitative work Also opens the door for faster chromatography Possibility of combo solvents/terpenes method with GC-VUV Needs testing on real world products 2018 Emerald Conference #emeraldconference