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©2011 Sigma-Aldrich Co. All rights reserved. SIGMA, SAFC, SIGMA-ALDRICH, ALDRICH, FLUKA, and SUPELCO are trademarks belonging to Sigma-Aldrich Co. and its a�liate Sigma-Aldrich Biotechnology, L.P. Sigma brand products are sold through Sigma-Aldrich, Inc. Sigma-Aldrich, Inc. warrants that its products conform to the information contained in this and other Sigma-Aldrich publications. Purchaser must determine the suitability of the product(s) for their particular use. Additional terms and conditions may apply. Please see reverse side of the invoice or packing slip.

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Dispersive SPE for “QuEChERS” Method

Prepacked Tubes - EN 15662:2008 - AOAC 2007.01

Customization Service

Bulk Adsorbents & Salts

Related Products

sigma-aldrich.com/quechers

Dispersive SPE for “QuEChERS” MethodQuick and simple sample cleanup for determination of pesticides in foods of plant origin according to EN 15662:2008 and AOAC 2007.01

l Efficient and economic sample cleanupl Pre-weighed amounts of sorbents and salts save labor and timel High-purity reagents from Sigma-Aldrichl Convenient and reliable in ready-to-use 12 mL centrifuge tubes

The QuEChERS Method (pronounced ‘catchers’) was developed by Lehotay & Anastassiades1 and stands for:

Quick, Easy, Cheap, Effective, Rugged, Safe

The method employs dispersive SPE (dSPE) and is a simple and fast method to cleanup food samples for pesticide analysis.

Main steps of the QuEChERS method are:

1. Homogenization of sample (with dry ice)2. Extraction of sample with internal standard added

using extraction solvent (e.g. acetonitrile), and pre-weight extraction/buffer salts

3. Shaking of sample and centrifugation4. Cleanup by transfer of an aliquot of supernatant

into a tube with bulk SPE material and additional salts5. Shaking of sample and centrifugation6. Transfer of aliquot, pH adjusted, to GC & LC-MS analysis

The main purification step in this method uses an adsorbent based on a primary and secondary amine phase (PSA), providing high capacity for removal of matrix components such as sugars, organic and fatty acids as well as polar pigments.

Depending on the sample matrix, in the fourth step the PSA in combination with magnesium sulfate may not be the only sorbent. For highly pigmented samples, a mix of PSA/MgSO4 and carbon and for fat-rich samples, a mix of PSA/MgSO4 and C18 silica is used. The carbon increases the binding capacity for pigments and the C18 silica removes higher amounts of lipids.

Prepacked TubesThe Supelco QuEChERS centrifuge tubes contain pre-weighed high quality salts and sorbents in those proportions described in the methods by M. Anastassiades and S. Lehotay. Anastassiades’ meth-od is formalized as European Standard Method EN 15662:2008 “Foods of plant origin – Determination of pesticide residues using GC-MS and/or LC-MS/MS following acetonitrile extrac-tion/ partitioning and cleanup by dispersive SPE – QuEChERS-method” while Lehotay’s method is formalized in AOAC Official Method 2007.01 “Pesticide Residues in Foods by Acetonitrile Extraction and Partitioning with Magnesium Sulfate”.

The product selection covers extraction tubes with salts for adjusting the pH during sample extraction with acetonitrile, cleanup tubes with PSA and MgSO4 and cleanup tubes with PSA, and additions of carbon or C18.

To read more about the dispersive SPE products and the QuEChERS method visit us at sigma-aldrich.com/quechers. Here you can

find in the Technical Resource section an overview chart (JWP), illustrating all steps of the QuEChERS EN Method as well as an application example of a “Intralab validation of the EN 15662 Method for the Determination of Pesticide Residues using a Fused- Core® column and Dispersive SPE (QuEChERS)”

References1. M. Anastassiades, S.J. Lehotay, D. Stajnbaher, F.J. Schenck, Fast and Easy

Multiresidue Method Employing Acetonitrile Extraction/Partitioning and “Dispersive Solid-Phase Extraction” for the Determination of Pesticide Residues in Produce, J. AOAC International, 2003, 86(22):412-431.

2. S.J. Lehotay, K. Mastovska, A.R. Lightfield, Use of Buffer and Other Means to Improve Results of Problematic Pesticides in a Fast and Easy Method for Residue Analysis of Fruits and Vegetables, J. AOAC International 2005, 88(2):615-629

3. S.J. Lehotay, Interlaboratory Validation of the QuEChERS Method to Analyze Pesticide Residues in Fruits and Vegetables, Proceedings AOAC Annual meeting, St. Louis, MO USA (2004)

4. EN15662:2008, Foods of plant origin - Determination of pesticide residues using GC-MS and/or LC-MS/MS following acetonitrile extraction/partitioning and cleanup by dispersive SPE - QuEChERS-method

5. AOAC Official Method 2007.01, Pesticide Residues in Foods by Acetonitrile Extraction and Partitioning with Magnesium Sulfate

Overview Chart - JWP

JWP

dSPE_Cit

Customization ServiceThe dispersive SPE approach is gaining popularity not only for foodstuffs but also for other sample matrices. Analysts may want to create custom mixtures of salts and adsorbents that might vary from the ones described in the QuEChERS method (EN15266:2008 or AOAC Official Method 2007.01) to fit their unique sample preparation challenges better. Supelco has introduced a custom service for these tubes that enables users to easily design their own dispersive SPE tube(s). Customers can choose from five different tube dimensions/types, as well as a large selection of adsorbents from Supelco, and salts from Fluka and Aldrich, to create customized tubes for introduction into their routine applications.

Please visit sigma-aldrich.com/custom-quechers for more detailed information on this service and download of the quote request form.

Dispersive SPE - Custom Quote Request

Contact Information

Name: ________________________________________________________________

Phone: _____________________________ Fax: ______________________________

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Fill out the information below and save the form. Submit as an attachment by email to: Supelco_Quotes@sial.com.

Or, print out the completed form and fax to 800-447-3044 (US, Canada) or to your local Sigma-Aldrich office.

Refer back to the Dispersive SPE Custom Services webpage for details on filling out this form.

Product Information

1. Select the desired hardware (please make only one selection).m 2 mL PP microcentrifuge tube m 12 mL PP centrifuge tube m 50 mL PP centrifuge tubem 4 mL glass vial m 22 mL glass vial

2. Select components to be packed. Enter bed weight in grams (Refer to dSPE Custom Services webpage for calculation details).Component Cat. No. Bed Weight (g)Magnesium sulfate 63135 ___________ g Sodium chloride 71379 ___________ gSodium citrate dibasic sesquihydrate 71635 ___________ gSodium citrate tribasic dihydrate 32320 ___________ gSodium acetate 24,124-5 ___________ gSodium bicarbonate S6014 ___________ gSupelclean PSA SPE 52738-U ___________ gSupelclean ENVI-Carb SPE 57210-U ___________ gDiscovery DSC-18 SPE 52600-U ___________ g

Supelco can pack components that are not listed above, but are available from Sigma-Aldrich/Supelco.

Other #1 (enter Sigma-Aldrich Cat. No.) ____________ ___________ g

Other #2 (enter Sigma-Aldrich Cat. No.) ____________ ___________ g

Other #3 (enter Sigma-Aldrich Cat. No.) ____________ ___________ g

3. Enter number of packs (1 pack = 50 tubes) ____________ packs

Additional comments / information

__________________________________________________________________________________________________________________________________

__________________________________________________________________________________________________________________________________

T509104

Print Form

Bulk Adsorbents and SaltsThe high-quality salts from Fluka and Aldrich as well as the Supelco adsorbents used for the pre-weighed tubes are also available as bulk chemicals. In the European Standard Method EN 15662:2008 the Fluka Magnesium Sulfate (Cat. No. 63135) is explicitly mentioned as suitable.

If you have any further questions, please do not hesitate to contact our local technical service representatives.

Pre-Packed Dispersive SPE (QuEChERS) Tubes

Description Qty. Cat. No.

EN15662:2008 (12 mL centrifuge tubes)Citrate Extraction Tube 50 55227-U 4 g MgSO4, 1 g NaCl, 0.5 g Sodium Citrate dibasic sesquihydrate, 1 g Sodium Citrate tribasic dehydratePSA SPE CleanUp Tube 1 50 55228-U 150 mg Supelclean™ PSA, 900 mg MgSO4

PSA/C18 SPE CleanUp Tube 1 50 55229-U 150 mg Supelclean PSA, 150 mg Discovery® DSC-18, 900 mg MgSO4

PSA/ENVI-Carb™ SPE CleanUp Tube 1 50 55230-U 150 mg Supelclean PSA, 15 mg Supelclean ENVI-Carb, 900 mg MgSO4

PSA/ENVI-Carb SPE CleanUp Tube 2 50 55233-U 150 mg Supelclean PSA, 45 mg Supelclean ENVI-Carb, 900 mg MgSO4

AOAC 2007.01 (12 mL centrifuge tubes)MgSO4/Acetate Extraction Tube 50 55234-U 6 g MgSO4, 1.5 g Sodium AcetatePSA SPE CleanUp Tube 2 50 55282-U 400 mg Supelclean PSA, 1200 mg MgSO4

PSA/C18 SPE CleanUp Tube 2 50 55283-U 400 mg Supelclean PSA, 1200 mg MgSO4, 400 mg DSC-18PSA/C18/ENVI-Carb SPE CleanUp Tube 50 55286-U 400 mg Supelclean PSA, 1200 mg MgSO4, 400 mg DSC-18, 400 mg ENVI-Carb

AOAC 2007.01 (2 mL centrifuge tubes)PSA SPE CleanUp Tube 2 100 55287-U 50 mg Supelclean PSA, 150 mg MgSO4

PSA/C18 SPE CleanUp Tube 2 100 55288-U 50 mg Supelclean PSA, 150 mg MgSO4, 50 mg DSC-18PSA/C18/ENVI-Carb SPE CleanUp Tube 100 55289-U 50 mg Supelclean PSA, 150 mg MgSO4, 50 mg DSC-18, 50 mg ENVI-CarbPSA/ENVI-Carb SPE CleanUp Tube 100 Custom 50 mg Supelclean PSA, 150 mg MgSO4,50 mg ENVI-Carb

Empty 50 mL Tubes for ExtractionEmpty Extraction Tubes (50 mL) 50 55248-U dSPE 50 mL empty Extraction Centrifuge Tubes

Bulk Adsorbents and Salts

Description Qty. Cat. No.

Supelclean PSA 100 g 52738-USupelclean ENVI-Carb 50 g 57210-UDiscovery DSC18 100 g 52600-UMgSO4 (as cited in EN 15662:2008) var. 63135Sodium citrate dibasic sesquihydrate var. 71635Sodium citrate tribasic dihydrate var. 32320Sodium chloride var. 71379Sodium acetate var. 241245

For other salts and adsorbents take advantage of the vast and comprehensive offering of Sigma-Aldrich at sigma-aldrich.com

TRADEMARKS: Ascentis, Discovery, Equity, ENVI-Carb, HybridSPE, SLB, Supelclean – Sigma-Aldrich Biotechnology LP; Empore – 3M Corporation; Fused-Core – Advanced Materials Technology, Inc.; Hettich – Hettich GmbH

60216-100g edit 63135b

T509104

Order/Customer Service (800) 325-3010 • Fax (800) 325-5052 Technical Service (800) 325-5832 • sigma-aldrich.com/techserviceDevelopment/Custom Manufacturing Inquiries (800) 244-1173Safety-related Information sigma-aldrich.com/safetycenter

Sigma-Aldrich® Worldwide O�ces

©2011 Sigma-Aldrich Co. All rights reserved. SIGMA, SAFC, SIGMA-ALDRICH, ALDRICH, FLUKA, and SUPELCO are trademarks belonging to Sigma-Aldrich Co. and its a�liate Sigma-Aldrich Biotechnology, L.P. Sigma brand products are sold through Sigma-Aldrich, Inc. Sigma-Aldrich, Inc. warrants that its products conform to the information contained in this and other Sigma-Aldrich publications. Purchaser must determine the suitability of the product(s) for their particular use. Additional terms and conditions may apply. Please see reverse side of the invoice or packing slip.

World Headquarters3050 Spruce St.

St. Louis, MO 63103(314) 771-5765

sigma-aldrich.com

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CanadaFree Tel: 1800 565 1400Free Fax: 1800 265 3858Tel: (+1) 905 829 9500Fax: (+1) 905 829 9292

ChileTel: (+56) 2 495 7395Fax: (+56) 2 495 7396

ChinaFree Tel: 800 819 3336Tel: (+86) 21 6141 5566Fax: (+86) 21 6141 5567

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DenmarkTel: (+45) 43 56 59 00Fax: (+45) 43 56 59 05

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VietnamTel: (+84) 3516 2810Fax: (+84) 6258 4238

Internetsigma-aldrich.com

Enabling Science to Improve the Quality of Life

SPE Products For a comprehensive listing of our SPE products, download our most recent SPE brochure at sigma-aldrich.com/spe under ”Learning Center”, or request your printed copy.

This brochure includes the most recently introduced

l HybridSPE®-Phospholipid for cleanup of plasma and serum samples for LC-MS

l Empore® line of SPE disk filters and cartridges

For more sample preparation & purification products (SPE, SPME, Flash Chromatography, Air Monitoring) visit our website: sigma-aldrich.com/sampleprep

Related Information and Products

Multilayer SPE TubesThe PSA and carbon adsorbent used in QuEChERS method are also available as packed SPE tubes.

For more details, please refer to sigma-aldrich.com/spe under “Multilayer SPE for Pesticide Analysis”, the Supelco catalog, or the SPE brochure.

Pesticide Standards and CRMsMore than 1300 pesticide & metabolite standards as well as Certified Reference Materials (CRMs) can be found on our web site: sigma-aldrich.com/pesticides

CentrifugesCentrifuges for use with the QuEChERS method can be found on our website: sigma-aldrich.com/analytical

The example shown on the right is the Hettich® EBA 21 Centrifuge (115V Cat. No. Z601136, 240V Cat. No. Z601128)

NLJT411065

More information on analytical products can be found at our website: sigma-aldrich.com/analytical

GC Columns For more details on our very low bleed SLB™-5ms or Equity®-1701 columns suitable for pesticide analysis, please refer to our website: sigma-aldrich.com/gc

0 10 20 30 40Min

HPLC Columns For more details on our highly efficient Ascentis® Express columns suitable for pesticide analysis, please refer to our website: sigma-aldrich.com/express. For an example application, please download “Intralab Validation of the EN 15662 Method for the Determination of Pesticide Residues Using a Fused-Core® Ascentis Express RP-Amide HPLC Column by LC-MS/MS and Cleanup by Dispersive SPE (QuEChERS)” from sigma-aldrich.com/quechers

G002462

Tracciato 200 molecole2

T402150D_cover-CMYK

G003676

P000126

z601136