Zoe Grosser, Vinson Leung, Jim Fenster, Brian LaBrecque Horizon Technology, Inc., Salem, NH USA

Transcription

1 Zoe Grosser, Vinson Leung, Jim Fenster, Brian LaBrecque Horizon Technology, Inc., Salem, NH USA

2 To develop an automated SPE method for the extraction of 20 organochlorine pesticides using an established, regulated manual-spe method for wine testing Demonstrate comparability of automation and manual SPE methodologies through good recoveries Show improvement or optimization to existing extraction methodology Establish an efficient workflow for transitioning from manual to automated SPE 2

3 Manual SPE Vacuum Manifold SmartPrep Extractor Automated SPE System 3

4 Condition Cleans sorbent bed and activates sorbent chemistry Load Introduces sample to sorbent to begin binding at consistent flow rate Wash Selectively removes interferences Elute Collects compounds in smallest volume for further analysis 4

5 ALCOHOL AND TOBACCO TAX AND TRADE BUREAU U.S. Department of the Treasury TTB routinely conducts pesticide analysis of domestic and imported wines Unauthorized pesticides or quantities outlined in FD&C Act, 21 U.S.C. 346a Authorizes EPA to set maximum residue levels for pesticides in/on foods Adulterated wines are determined by consultation with EPA and FDA based on determined pesticides and levels 5

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7 Matrix BAREFOOT Moscato (ALC. 9%) Livingston Cellars Chardonnay (ALC. 12%) Cartridges Waters Oasis HLB 6 cc, 200 mg Supelco Aminopropyl LC-NH2 3 cc, 500 mg Solvents 50:50 Ethyl Acetate:Hexane 80:20 Ethyl Acetate:Hexane Methanol Dionized Water Pesticide Spike Restek #32415 Other Magnesium Sulfate 7

8 Aldrin ( ) α-bhc ( ) β-bhc ( ) δ-bhc ( ) γ-bhc (Lindane) ( ) cis-chlordane ( ) trans-chlordane ( ) 4,4 -DDD ( ) 4,4 -DDE ( ) 4,4 -DDT ( ) Dieldrin ( ) Endosulfan I ( ) Endosulfan II ( ) Endosulfan sulfate ( ) Endrin ( ) Endrin aldehyde ( ) Endrin ketone ( ) Heptachlor ( ) Heptachlor epoxide (isomer B) ( ) Methoxychlor ( ) 8

9 Modified TTB Method Procedure 1. Mix 20 ml wine with 20 ml DI Water (total volume 40 ml) 2. Spike sample with 50 µl of pesticide mix (50 µg/ml) 3. Condition Oasis HLB cartridge with 10 ml of: i. 50:50 Ethyl Acetate:Hexane ii. Methanol iii. DI Water 4. Load sample at 5 ml/min and vent remaining sample of 1.1 ml to cartridge 5. Air dry for 10 mins 6. Elute cartridge with 5 ml of i. 80:20 Ethyl Acetate:Hexane ii. 50:50 Ethyl Acetate:Hexane iii. 50:50 Ethyl Aceate:Hexane 7. Load aminopropyl cartridge with 1/3 column volume of magnesium sulfate (drying agent) 8. Condition aminopropyl cartridge with 5 ml 50:50 Ethyl Acetate:Hexane 9. Load and collect extract 10. Evaporate with XcelVap to 1.0 ml TTB Method Procedure 1. Mix 20 ml wine with 20 ml DI Water (total volume 40 ml) 2. Spike sample with 50 µl of pesticide mix (50 µg/ml) 3. Condition Oasis HLB cartridge with 10 ml of: i. 50:50 Ethyl Acetate:Hexane ii. iii. Methanol DI Water 4. Load sample by gravity (initial vacuum pull) 5. Air dry for 15 mins 6. Elute cartridge with 5 ml of i. 80:20 Ethyl Acetate:Hexane ii. iii. 50:50 Ethyl Acetate:Hexane 20:80 Ethyl Aceate:Hexane 7. Load aminopropyl cartridge with 1/3 column volume of magnesium sulfate (drying agent) 8. Condition aminopropyl cartridge with 5 ml 50:50 Ethyl Acetate:Hexane 9. Load and collect extract 10. Evaporate with Nitrogen to 0.1 ml 11. Add 1 ml 0.1% corn oil/etoac 9

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11 Sample line rinse Sample bottle rinse 11

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14 OVEN Initial temp: 70 'C Initial time: 0.50 min Ramps: # Rate ( /min) Final temp Final time C C C 3.00 FRONT INLET (SPLIT/SPLITLESS) Mode: Pulsed Splitless Initial temp: 245 C Pressure: 8.71 psi Pulse pressure: 25.0 psi Pulse time: 1.00 min Gas type: Helium COLUMN 1 Capillary Column Model Number: Phenomenex ZB-SemiVolatiles Nominal length: 30.0 m Nominal diameter: µm Nominal film thickness: 0.25 µm Mode: constant flow Initial flow: 1.0 ml/min MSD Transfer Line Heater held at 325 C GC Injector Injection Volume 1.00 microliters 14

15 Manual Manifold SmartPrep Compounds Water Wine (Moscato) Water Wine (Moscato) a-hch b-hch g-hch d-hch Heptachlor Aldrin Heptachlor epoxide (B) t-chlordane c-chlordane Endosulfan I ,4`-DDE Dieldrin Endrin Endosulfan II ,4`-DDD Endrin Aldehyde Endosulfan Sulfate ,4`-DDT Endrin Ketone Methoxychlor

16 Manual Manifold SmartPrep Manual Manifold SmartPrep Compounds Water Water Wine (Moscato) Wine (Moscato) a-hch b-hch g-hch d-hch Heptachlor Aldrin Heptachlor epoxide (B) t-chlordane c-chlordane Endosulfan I 4,4`-DDE Dieldrin Endrin Endosulfan II 4,4`-DDD Endrin Aldehyde Endosulfan Sulfate 4,4`-DDT Endrin Ketone Methoxychlor Statistics MEAN STDEV %CV MEAN STDEV %CV MEAN STDEV %CV MEAN STDEV %CV

17 SmartPrep Compounds Wine (Moscato) Wine (Chardonnay) a-hch b-hch g-hch d-hch Heptachlor Aldrin Heptachlor epoxide (B) t-chlordane c-chlordane Endosulfan I 4,4`-DDE Dieldrin Endrin Endosulfan II 4,4`-DDD Endrin Aldehyde Endosulfan Sulfate 4,4`-DDT Endrin Ketone Methoxychlor

18 Compound: Endrin Aldehyde Wine Matrix: Moscato Mean % Recovery: 53% Compound: Endrin Aldehyde Wine Matrix: Chardonnay Mean % Recovery: 18% 18

19 Manual Manifold vs. SmartPrep Demonstrated comparability - automation and manual SPE Horizon Technology SmartPrep Extractor produced comparable recoveries to manual Manual Manifold SmartPrep Manual Manifold SmartPrep Water Wine (Moscato) MEAN STDEV %CV MEAN STDEV %CV MEAN STDEV %CV MEAN STDEV %CV Established efficient workflow from manual to automated SPE SmartPrep software enabled consistent programming to TTB method Automated SPE and bottle rinsing process XcelVap performed consistent sample eluent dry-down Results show there is a likely wine matrix effect Affecting recoveries of certain compounds vs. water recoveries Room for improvement with future SPE optimization Moscato vs. Chardonnay Higher sugar content may hinder recoveries (approx. 10% difference) 19

20 Index M Index A Index B Index C Index D Index E Index F Index G Index I Index K Index H Index J Index L 20

21 Achieve higher recoveries by resolving matrix effect with optimization Automate the optimization process using the SmartPrep software Test elution flow rates and elution volumes to determine optimal values Use optimal values to test elution solvents for 1 st and 3 rd fractions Elution Flow Rates 10 ml/min 7 ml/min 5 ml/min Elution Volumes 5 ml 7 ml 1 st Elution Solvent 80:20 EtOAc:Hexane To 75:25 EtOAc:Hexane 85:15 EtOAc:Hexane 3 rd Elution Solvent 50:50 EtOAC:Hexane To 35:65 EtOAc:Hexane 25:75 EtOAc:Hexane 21

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