The Use of Dispersive Solid Phase Extraction in the Detection of Pesticides in Cannabis Flower by GC-MS/MS February 21, 2021 Application Note, GC Triple-Quad MS, Mass Spectrometry (MS) 0 Adam Floyd1, Kirk R. Jensen2, Craig D. Sergeant2, A. John Dane2, Josh Cosgrove1, and Mike Tunis1 1Think20 Laboratories, Irvine, CA 2JEOL USA, Inc. Peabody, MA INTRODUCTION As recreational and medical cannabis use becomes legalized in more jurisdictions, more pesticides are being used in the cultivation of Cannabis. Because certain pesticide residues can pose significant health risks to consumers, pesticide analysis of Cannabis in California is highly regulated by the Bureau of Cannabis Control (BCC). All legal Cannabis products sold in California must undergo analysis for sixty-six regulated pesticides. The action limits of these pesticides vary depending on their classification and perceived danger to human health. Extracted Cannabis matrix is notoriously difficult to work with as there are significant interferences present which hinder the low-level detection of pesticides. This study presents a comprehensive method for the analysis of gas chromatograph (GC)-amendable pesticides in Cannabis flower. Furthermore, this method uses dispersive solid phase extraction (dSPE) to help mitigate matrix effects that are common in the flower extract. Three selected reaction monitoring (SRM) transitions were used for each target pesticide. This study was focused on developing a robust and sensitive method for GC amendable pesticides in Cannabis flower for use in the state of California. However, LC-MS/MS would also be required to analyze the complete California pesticide list. EXPERIMENTAL Sample Preparation: Cannabis flower was ground and extracted using a mixture of acetonitrile and dimethylacetamide (DMA). The sample was spiked with a 20 ppb pesticide standard mixture consisting of the 12 compounds listed in Table 3. The extraction and dSPE workflow are outlined in Figure 1. The use of dSPE is critical for reducing matrix effects and allowing for low detection limits as shown in Figure 2. Fig 1. Sample preparation of Cannabis flower. Fig 2. Cannabis matrix effects before (top) and after (bottom) using dSPE. Table 1: Gas Chromatograph Parameters Table 2: Mass Spectrometer Parameters Instrumentation: An Agilent 7890B GC combined with a JEOL JMS-TQ4000GC triple quadrupole mass spectrometer was used in this study. All injections were done using pulsed splitless liquid injection. Analysis parameters and SRM channels are detailed in Tables 1–3. RESULTS The SRM chromatograms for the three transitions of every pesticide tested are shown in Figures 3 – 14. Strong signals were observed for all pesticide transitions at 20 ppb with very little interference effects. These results clearly show that this extraction/dSPE method combined with GC-MS/MS can readily handle the action limits for GC amenable pesticides as set forth by California regulations. CONCLUSIONS This study showcases a rapid, sensitive, and effective method for testing GC amenable pesticides in Cannabis matrix. The use of a dSPE sample cleanup step coupled with GC-MS/MS allows for the rapid, selective screening of Cannabis products. Furthermore, low detection limits were achieved using this scenario, which in turn allows for larger dilution factors to further mitigate matrix effects. Using dSPE also allows for greater sensitivity and better chromatographic peak shapes by removing interference compounds. These results show that each pesticide can be measured at 20 ppb in cannabis matrix and that the action limits put forth by the State of California are readily achievable using this method. Furthermore, a combination of GC-MS/MS and LC-MS/MS will provide the best all-around capabilities for analyzing the entire California pesticide list. Table 3: SRM Transitions Fig 3. SRM chromatograms for boscalid. Fig 4. SRM chromatograms for cis-chlordane Fig 5. SRM chromatograms for trans-chlordane. Fig 6. SRM chromatograms for chlorfenapyr. Fig 7. SRM chromatograms for fipronil. Fig 8. SRM chromatograms for kresoxim-methyl. Fig 9. SRM chromatograms for methiocarb. Fig 10. SRM chromatograms for propoxur. Fig 11. SRM chromatograms for chlorpyrifos. Fig 12. SRM chromatograms for diazinone. Fig 13. SRM chromatograms for dimethoate. Fig 14. SRM chromatograms for pentachloro-nitrobenzene (PCNB). For full details: Attached files often contain the full content of the item you are viewing. Be sure and view any attachments. Think20 JEOL Dispersive SPE in Pesticides in Cannabis Flower Formatted 2-12-2021_JD.pdf 1.87 MB Related Articles Analysis of Pesticides in a Hemp Matrix Hemp is a strain of Cannabis sativa that has multiple industrial uses including paper, plastics, woven goods, and even food. While certain strains of Cannabis sativa are well-known for their use as a recreational drug due the presence of the psychoactive compound tetrahydrocannabinol (THC), hemp strains are defined by the U.S. federal government as those that contain less than 0.3% THC.1 Additionally, hemp strains typically contain more cannabidiol (CBD),2 which was recently approved by the FDA to treat certain types of epilepsy, and is currently being investigated as a medical treatment for other afflictions. Analysis of Scotch Whiskey and Tequila Samples by Solid-Phase Microextraction and High-Resolution GC/MS Solid-phase microextraction (SPME) is a convenient sample preparation method for extracting organic compounds from aqueous samples. The combination of SPME with gas chromatography and high-resolution mass spectrometry provides powerful capabilities for the analysis of alcoholic beverages. Two samples of Scotch whiskey and one tequila sample were sampled by using solid-phase microextraction for analysis by high-resolution GC/MS. Sample 1 was a blended 12-year old light Scotch whiskey, while sample 2 was a 12-year old single-malt light Scotch whiskey. The tequila sample was a popular brand that is widely sold in the USA. Compounds were extracted and identified by GC/MS with library search. Exact mass measurements provided elemental compositions for molecular ions and fragment ions. Analysis of Coffee Aroma Compounds by Headspace Solid-Phase Microextraction (SPME) GC-MS with the JMS Q1500GC Master-Quad GC-MS System The composition of volatiles from freshly ground roasted coffee is complex, with hundreds of chemical compounds contributing to the aroma. Headspace solid-phase microextraction was used to sample volatiles from five different coffees for analysis by GC-MS. Chemometric analysis revealed specific differences between coffees from different origins and different preparations. Using Solid Phase Microextraction with AccuTOF-DART for Fragrance Analysis Solid phase microextraction (SPME) is a well established sampling technique that is often used to isolate volatile organic components in gaseous mixtures. Once the compounds have been collected, the SPME fibers are typically placed into a heated GC inlet which thermally desorbs these components into a GC-MS system for analysis. Normally, this analysis can take between 10 and 30 minutes to complete depending on the complexity of the samples. In this work, the Direct Analysis in Real Time (DART™) heated gas stream is used to desorb and directly introduce a SPME sample into a high-resolution mass spectrometer. This methodology produces comparable information to the traditional GC-MS technique but streamlines the results into only a few seconds of analysis time. Analysis of Fermentation Gas from Home-Brewed Beer by Solid-Phase Microextraction (SPME) and GC/MS Fermenters used for home beer brewing are fitted with an airlock consisting of a liquid barrier that permits the fermentation gases to escape while preventing contamination from atmospheric microbes. Large volumes of carbon dioxide are produced during the most vigorous stages of fermentation, which can occur as early as the first 24 hour period after an ale yeast is added (pitched) to the sweet liquid (wort) produced from barley during the initial mashing step. The gases emitted from the airlock can have a pleasant aroma that can be quite distinctive during the initial stages of fermentation. Solid-phase microextraction (SPME) combined with gas chromatography/mass spectrometry (GC/MS) was used to determine the volatile components contained in the fermentation gas. Analysis of Pesticides in a Cannabis sativa Matrix JEOL msPrimo and Escrime software provide all of the tools needed to develop optimized methods for target compound quantitation and report generation. In this application note, we describe a sensitive method for analyzing pesticides in Cannabis sativa matrix using the SRM capabilities of our triple quadrupole system. Showing 0 Comment Comments are closed.