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Results are reported in Aim 2. Goal: To develop a sampling protocol in order to use solid-phase microextraction (SPME) to capture aerosol produced by an e-cigarette for analysis by a SPME GC-MS and SPME-DARTMS methods in order to both qualitatively and quantitatively assess the amount of nicotine and flavoring agents found in e-cigarette aerosol. Results: Polydiethylsiloxane (PDMS) SPME fibers were demonstrated to successfully capture nicotine and flavoring agents in concentrations that were analyzed by GC-MS and DART-MS. The aerosol produced by the e-cigarette was trapped with the apparatus described above. A 7μm or 10 μm PDMS SPME fiber was inserted through a stopper in the first trap, depending on the molecular weight of the drug. The fiber was introduced into the trap while the e-cigarette was activated for four seconds, aerosolizing 7-10 µL and the aerosol filled the trap. The SPME fiber was held in the trap for five minutes, after which the fiber was removed. The SPME fiber was then inserted into the injection port of an Agilent GC-MS 6890N/5973 Mass Selective Detector with an HP-5MS column 30 m × 0.25 mm id × 0.25 µm. The injection port was set to 315 °C and the run was made in splitless mode with a 15-minute thermal desorption time. The initial temperature was set to 120 °C, with a ramp to 300 °C at 10 °C/min, with a hold time of 12 min at 300 °C, for a total run time of 30 min. The fibers were thermally cleaned between runs to ensure no carryover occurred between samples. (Figure 2). Alternatively, the SPME fiber was waved in the helium stream of the DART-MS following previously validated methods. The analysis was performed in positive-ion mode with a helium stream temperature of 300 °C. The ion guide peak voltage was 400 V, reflectron voltage was 900 V, orifice 2 was set to 5 V, and the ring lens was set to 3 V with orifice 1 operated in function switching mode at 20, 60, or 90 V with a single data file created for all three voltages. The range of masses measured was from 40 to 1100 Da. (Figure 3). The general analytical scheme adopted in the laboratory was that all e-liquids were screened by DART-MS. Samples were then quantitated by GC-MS or LC-MS/MS. Samples were aerosolized and active ingredients were extracted by SPME for analysis by DART-MS and GCMS in order to demonstrate that pharmacologically active ingredients were in the vapor. See Figure 4 for examples. 7 This resource was prepared by the author(s) using Federal funds provided by the U.S. Department of Justice. Opinions or points of view expressed are those of the author(s) and do not necessarily reflect the official position or policies of the U.S. Department of Justice. Experiment 3. Quantify nicotine and adulterant pharmaceuticals by LCMS3 Goal: Validated method for nicotine and Drugs Other Than Nicotine (DOTNs) by LCMS3 Results: The nicotine concentrations of the e-liquids were determined using HPLC-MS/MS with a Hypersil® Gold 3x50 mm, 5 µm column and a method previously published. The mobile phase consisted of 1:9 DI water with 10 mmol ammonium acetate and 0.1% formic acid: methanol, and was run at an isocratic flow rate of 0.5 mL/min. The injection volume was 10 µL. The ion spray voltage was 5000 V and the source temperature was 600 °C with 30 mL/min curtain gas flow. The instrument was operated in multiple reaction monitoring mode (MRM) monitoring the following m/z transitions: nicotine, 163>130 and 163>117; and nicotine-d4, 167>134. A linear regression was plotted of peak area ratio of nicotine to internal standard versus nicotine concentration. A method for quantitation of methamphetamine was validated using an Agilent 6890N Gas Chromatograph coupled to a 5973 Mass Selective Detector per SWGTOX guidelines. Chromatographic separation was performed on a HP-5MS column 30 m x 0.25 mm id x 0.25 mm (Agilent, Santa Clara, CA). The GC/MS was operated in a split mode at a ratio of 6:1, with 1 µL injection volume. The carrier gas was helium at a linear velocity of 35 cm/s. The GC had an oven temperature of 120 °C-200 °C at a rate of 10 °C/min then ramped to 280 °C at a rate of 30 °C/min. The MSD was operated in SIM mode with 58, 64, 91, 96, 134 m/z as the selected ions. Quantification was performed using 58 and 64 m/z as the quantitative ions for methamphetamine and methamphetamine-d11, respectively. The qualitative ions for methamphetamine were 91 and 64 m/z and 91 m/z for methamphetamine-d11. The total run time of 10.67 minutes. A six-point calibration curve was constructed with methamphetamine concentrations of 100, 200, 500, 750, 1000, and 2000 ng/mL with 500 ng/mL of methamphetamine-d11 as internal standard. The calibration curve was matrix-matched and was extracted from water using the method previously described. A linear regression was
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