1. Evolution GC-MS/MS: Pesticide analysis in canola oil Evolution GC-MS/MS: Pesticide analysis in canola oil Vivian Watts 1, Ingo Christ 1, Mark Misunis 2 and Wendy Cheung 2 1) Chromsys LLC, P.O. Box 15131, Alexandria, VA 22309, USA 2) Canadian Food Inspection Agency, 3650 36 th Street, N.W., Calgary, Alberta T2L 2L1, Canada The addition of a proprietary 90° vertical collision cell and another high precision quadrupole - serving as mass filter Q3 – converts the Agilent 5973 or 5975 MS system to a Triple Quadrupole instrument, the EVOLUTION. When using a Single Quadrupole instrument for fish and canola oil analysis, matrix interferences caused several of the pesticides to be challenging to quantitate accurately. In the data presented here, canola oil has been analyzed on the Evolution-upgraded Triple Quadrupole GC-MS using the highly sensitive and specific MS/MS mode “Selected Reaction Monitoring” (SRM), also known as MRM. On the Evolution, ion ratios were more stable than on the standard Single Quadrupole system, even between widely different pesticide concentration levels (data not shown). Furthermore, detection limits were far lower than on the Single Quadrupole instrument, especially for the pesticides Aldrin (ALD), oxy-chlordane (OXL), Dieldrin (HEO) and Endrin (END). As a result, we have more confidence in the identification and quantitation of pesticides in canola oil matrix when using the Triple Quad-upgraded instrument. GC-MS/MS is a highly effective technique for analyzing complex/dirty sample matrices. Sensitivity and accuracy are superior to conventional GC-MS due to higher signal to noise ratios and less interference. This is the result of virtually eliminating matrix interferences when running in SRM mode. Fish and vegetable oil samples which are routinely analyzed for pesticide residue, typically have particularly complex matrices for which SIM mode is not always sufficient. The experiment involved the determination of 16 pesticides in canola oil in single quadrupole mode (SIM) and Triple Quadrupole mode (Selected Reaction Monitoring or SRM). SRM involves choosing a precursor ion – product ion combination for each analyte where the first quadrupole (Q1) is set up to monitor the precursor ion and the third quadrupole (Q3) monitors the product ion. This is called a transition and helps to enable great sensitivity with very little matrix interference. The SRM data were compared to data with an existing SIM method for which, although many compounds could be analyzed satisfactorily, the sensitivity was not always enough. Aldrin, Oxy-chlordane, Dieldrin and Endrin were particularly problematic and lower detections limits were desired. Canola oil (2 g) was spiked with a known amount of the 16 pesticides and an internal standard, endo-heptachlor epoxide. After gel permeation chromatography (GPC) and solvent extraction, the pesticides were extracted with Solid Phase Extraction and the extract injected into the GC. Abstract Introduction Experimental Results (Single Quadrupole) Conclusions Method Triple Quadrupole parameters GC - Parameters: Sample Volume: 1 µL GC Model: Agilent 6890N (Agilent Technologies, Wilmington, DE) Column: GL Scientific InertCap 5ms 40m x 0.18mm x 0.18µm (MS/MS) and Agilent DB-1701P 30m x 0.25mm x 0.25  m (MS) Carrier gas: He, constant flow of 1.4 mL/min (MS/MS) and constant pressure of 15.8 psi. (MS). Inlet Mode: Splitless Inlet Temp.: 250 °C MS parameters: MS: Agilent Technologies 5973, upgraded to Chromsys Evolution Triple Quad (MS/MS ) and Agilent Technologies 5973 (MS) Source mode: EI, 70 eV MS/MS Collision gas: Argon at 14 psi. EMVolts: 2576 V (MS/MS) and 1811 (MS) Further Information Please contact info@chromsys.com. More information and application notes can be obtained at http://www.chromsys.com/ Evolution MS/MS system Table 1: The 16 pesticides, and transitions and collision energies used for MS/MS analysis. Fig. 1: System upgraded to Evolution GC-MS/MS The Evolution MS/MS upgrade for the Agilent 5973 and 5975 is able to produce far lower detection limits in a complex matrix such as that of canola oil. Although SIM mode often was sufficient for many compounds in this matrix, interference was a problem especially for four pesticides. MS/MS was a major step improvement for obtaining accurate, precise and reliable results. Figures 3 and 4 show SIM peaks for 10 ppb spikes (into sample, before extraction) in canola oil matrix for the above-mentioned four pesticides. Dieldrin (HEO) could not be quantified at the 10 ppb spike level and S/N ratios were low.. Fig. 2: Inside the Evolution Triple Quad: Agilent source, quadrupole 1, and detector and a curved 90° collision cell and quadrupole 3. Results (Triple Quadrupole) Rt (min)CompoundAbbreviationSRM 1SRM 2Coll. Energy (eV) 8.04alpha-BHCBHD219>182183>14710 ; 15 8.23HexachlorobenzeneHXB284>249286>21415 ; 15 8.54beta-BHCBHE219>183181>14515 ; 15 8.69LindaneLIN219>183181>14515 ; 15 9.2delta-BHCBHG219>183183>14715 ; 15 10.63HeptachlorHEP272>237272>23515 ; 15 11.87AldrinALD263>227263>19115 ; 15 13.6endo-heptachlor epoxidec-HEX353>262353>28018 ; 18 13.67Oxy-chlordaneOXL185>121 10 13.82exo-heptachlor epoxidet-HEX253>252253>21718 ; 18 14.88cis-chlordaneCHC375>266375>26515 ; 15 16.524,4'-DDEDDE246>175316>28115 ; 15 16.61DieldrinHEO263>227265>23015 ; 15 17.17EndrinEND263>227263>19230 ; 30 17.574,4'-DDDTDP235>165237>16515 ; 15 18.324,4'-DDTDDP235>165237>16515 ; 15 20.57MirexMIR271>237273>23710 ; 10 Figure 4. Oxy-chlordane and Dieldrin at 10 ppb (SIM mode with Single Quad) Figure 5. Aldrin, Dieldrin and Endrin at 10 ppb (SRM mode with Chromsys Evolution Triple Quad.) Figure 6. oxy-chlordane at 10 ppb (SRM mode with Chromsys Evolution Triple Quad) Figure 3. Aldrin and Endrin at 10 ppb (SIM mode with Single Quad) Compared to the Single Quadrupole, the Evolution Triple Quadrupole upgraded instrument enabled far lower minimum reporting levels (the lowest level that can be reported with confidence) for at least four pesticides: Aldrin (ALD), oxy-chlordane (OXL), Dieldrin (HEO) and Endrin (END). Figures 5 and 6 show SRM (MRM) peaks for 10 ppb spikes (into sample, before extraction) in canola oil matrix for the above-mentioned four pesticides. Dieldrin (HEO) was easily quantified at the 10 ppb spike level.