AOAC 133rd Annual Meeting - Final Program

Poster Abstracts | Tuesday

within different sections of each single plant. Our objective was to compare variability within a plant as well as accuracy of compositing samples. Flower samples were collected in the field, from 3 sections of the plant, the top, middle, and bottom of each plant. Each section sample was individually homog- enized, and a separate composite sample was homogenized using the 3 section samples. All samples were extracted and placed into headspace vials for analysis. Analysis of the terpene profiles were performed using PerkinElmer Headspace/Gas Chromatography/Mass Spectrometry (GC-MS), to quantita- tively determine the terpenes that were present. Terpene profiles of the 3 sections for each plant were compared to each other as well as compared to the composited sample. Presenter: Carly Barone, Bia Diagnostics LLC, Colchester, VT, USA, Email: carly@biadiagnostics.com P-T-044 Michael Young , Kim Tran , Kari Organtini , Waters Corp., Milford, MA, USA Meeting Regulatory Limits for Pesticide Residues in Cannabis: Extraction and Cleanup Strategies for LC-MS/ MS and GC-MS/MS Analysis Multi-residue pesticide methods for cannabis must provide reli- able and robust quantitative analysis to meet regulatory limits for the entire list of required analytes. The sensitivity and specificity offered by LC-MS/MS is suitable for the determination of most pesticide residues in cannabis. However, not all pesticides ionize efficiently by the electrospray or atmospheric pressure chemical ionization modes typically used for LC-MS. Fortunately, most of the pesticides with very low LC-MS sensitivity have much better response using GC-MS analysis. Therefore, the application of both LC-MS/MS and GC-MS/MS will achieve the lowest possi- ble detection limits for the widest range of pesticide residues. As important as the instrumental considerations for pesticide residue analysis in cannabis are the considerations for sample preparation. Various extraction procedures were investigated and both dispersive and pass-through types of SPE cleanup were evaluated. Methods were developed for multi-residue pesticide analysis in cannabis using both LC-MS/MS and GC-MS/MS after optimized extraction and cleanup. Method performance was evaluated by assessing recovery, matrix suppression, linear- ity, and sensitivity. Presenter: Michael Young, Waters Corp., Milford, MA, USA, Email: michael_s_young@waters.com P-T-045 Jennifer Salmons , Mike Tanner , Jeff Wiseman , J2 Scientific, LLC, Columbia, MO, USA Automated Preparation Method for the Determination of Mycotoxins and Residual Pesticides/Herbicides in Cannabis The majority of states that have legalized the medicinal and/or recreational use of cannabis require testing of the end product to monitor mycotoxins and any residual pesticides/herbicides that may have been applied during plant growth. An automated gel

permeation chromatography (GPC) with SPE cleanup method was developed where the cannabinoids, major constituents of the end product, are fractionated from the trace-level concen- trations of mycotoxins and pesticides/herbicides. This allowed the cannabinoids to be measured directly in the first fraction, and the trace-level mycotoxins and pesticides/herbicides to be measured in a second, more concentrated fraction. Since Missouri has not legalized recreational cannabis use, ground hops were used as a surrogate. Following automated concentra- tion, the samples were automatically directed to pre-conditioned SPE cartridges for additional cleanup and fractionation prior to sample concentration and solvent exchange. Analyses were performed by reversed phase high performance liquid chroma- tography with fluorescence and variable wavelength detection (HPLC-FL/VWD). The automated method resulted in a less labor-intensive fractionation procedure with lower variabil- ity between results when compared to manual techniques. It also separated the high-concentration cannabinoids from the trace-level constituents, resulting in fewer chromatographic inter- ferences when quantifying at low-levels. Presenter: Jennifer Salmons, J2 Scientific, LLC, Columbia, MO, USA, Email: jsalmons@j2scientific.com P-T-046 Julia Bramante , Heather Krug , Marijuana Reference Laboratory, Denver, CO, USA There is More Than Meets the Eye: The Complexities of Detecting Pathogens in the Cannabis Matrix A method validation was designed and conducted to verify and extend the scope of the method validation under AOAC Certificate No. 010803, iQ-Check Salmonella II Real-Time PCR, and AOAC Certificate No. 121203, iQ-Check STEC VirX and SerO Real-Time PCR, manufactured by Bio-Rad Laboratories, the performance claim of each is to allow for the detection of Salmonella spp. and Shiga toxin producing E. coli (STEC) from food samples utilizing real-time PCR technology, respectively. Specifically, this method validation extends the scope of matrices in the initial method validations to include naturally contaminated cannabis flower. In addition, this study evaluated a method modification to the initial method validations by harmonizing the Salmonella spp. and STEC sample enrichment steps, utilizing buffered peptone water for both method sample enrichments. Confirmation of samples was performed using a modified FDA BAM Salmonella and STEC protocol, including CHROMagar™ and secondary, selective enrichment comparisons. Where possible, the overall study was designed to incorporate Appendix J: AOAC International Methods Committee Guidelines for Validation of Microbiological Methods for Food and Environmental Surfaces, including data analysis and applied statistical methodology to determine most probable number, probabilities of detection, and method comparisons. Presenter: Julia Bramante, Marijuana Reference Laboratory, Denver, CO, USA, Email: julia.bramante@state.co.us

70 SEPTEMBER 6–12, 2019 SHERATON DENVER DOWNTOWN HOTEL