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404 Error ? OK ! IF “%20” > then delete ! or replace THE “%20” with “-” (a minus!) in the URL above & >< !
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mini-SHOPPE proto-Shop2CT > “OUR Consensus” > CC > GW & Energy BLOGs > & some politics !
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OEM (& Restek ! ) Literature generally is updated regularly > ”OLDER” material on this Site is for Our “archive”€ Purposes - and as a Customer TECHNICAL Resource for U ! & >Your Subscription to Restek see Restek Catalogs > 2009-10, 2011-2, 2015-6 > but some items no longer available / superseded ! : ASK ! Printed Catalogs R NO LONGER AVAILABLE from Restek ! ( latest was 2015-16 ! > & here on-line ! )
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Restek QuEChERS Products Quick Easy Cheap Effective Rugged & Safe
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SPE Cleanup Techniques using Multiple Adsorbents for GC and HPLC
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Internal Standards and Quality Control Standards
- Single and multiple component standards as specified in
EN Method 15662
- Support for GC and HPLC with MS, MS/MS, and selective detectors.
- Ready to use QuEChERS extractions no dilutions necessary Products
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Restek Quechers - Methodology Overview Restek On-line Presentation - Slide Show / audio Product Overview PDF ask for detail Lit . . . reviewed
![Quechers-SPE Quechers-SPE](./Quechers-SPE_1.jpg)
![Q-Sep2 Q-Sep2](./Q-Sep2_1.jpg)
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Tubes for Extraction and Clean-up of Pesticide Residues from Food Products
- Fast, simple sample extraction and cleanup using dSPE
- Fourfold increases in sample throughput
- Fourfold decreases in material cost
- Convenient, ready to use centrifuge tubes with ultra pure, preweighed adsorbent mixes
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Quick, Easy, Cheap, Effective, Rugged, and Safe
the QuEChERS ("catchers") method is based on work done and published by the US Department of Agriculture Eastern Regional Research Center in Wyndmoor, PA.(1) Researchers there were looking for a simple, effective, and inexpensive way to extract and clean pesticide residues from the many varied sample matrices with which they routinely worked. They had been using the Modified Luke Extraction Method, which is highly effective and rugged, but is both labor and glassware intensive, leading to a relatively high cost per sample. Solid phase extraction also had been effective, but the complex matrices the investigators were dealing with required multiple individual cartridges and packings to remove the many classes of interferences, adding costs and complexity to the process.
A new method would have to remove sugars, lipids, organic acids, sterols, proteins, pigments and excess water, any of which often are present, but still be easy to use and inexpensive.
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The researchers developed a simple two-step procedure. (1) the homogenized samples are extracted and partitioned, using an organic solvent and salt solution. Then, the supernatant is further extracted and cleaned, using a dispersive SPE technique. Multiple adsorbents are placed in a centrifuge tube, along with the 1mL of organic solvent and the extracted residues partitioned from step 1. The contents are thoroughly mixed, then centrifuged, producing a clean extract ready for a variety of GC or HPLC analytical techniques .(2) Validation and proficiency data for the QuEChERS method are available for a wide variety of pesticides in several common food matrices at www.quechers.com
Using the dispersive SPE approach, the quantity and type of adsorbents can be easily adjusted for differing matrix interferences and "difficult" analytes. Results from this approach have been verified and modified at several USDA and Food and Drug Administration labs, and the method now is widely accepted for many types of pesticide residue samples.
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Restek Q-sep products make the QuEChERS approach even simpler. Extraction salts are preweighed and provided with 50mL centrifuge tubes. The dSPE centrifuge tubes, available in 2mL and 15mL sizes, contain magnesium sulfate (to partition water from organic solvent) and PSA* adsorbent (to remove sugars and fatty acids), with or without graphitized carbon black (to remove pigments and sterols) or C18 (to remove nonpolar interferences). Custom products are available by quote request. If you are frustrated by the time and cost involved with your current approach to pesticide sample extraction and cleanup, we suggest you try this simple and economical new method.
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Restek has products compliant with AOAC, Multi-miniresidue and European methods. Click here for our complete Q-sep QuEChERS product listing.
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Did You Know?
- Multiple sorbents are used to remove different types of interferences.
- MgSO4 - removes excess water
- PSA* - removes sugars, fatty acids, organic acids, and anthocyanine pigments
- C18 - removes nonpolar interferences
- Carbone- removes pigments, sterols, and nonpolar interferences
*PSA - primary and secondary amine exchange material.
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![Q-Sep3 Q-Sep3](./Q-Sep3.gif) |
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QuEChERS Standards & SPE Tubes
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Restek & Biocomma Quechers EN15662 are to the same “nominal” Methodology Specs Specific Individual Method Apps may applies ! Pricing Difference is significant ) ORDER the appropriate Cat.#s
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![FLIP-HTML5 FLIP-HTML5](./FLIP-HTML5_209.jpg) Restek & Biocomma FlipHTML5 Catalogs 69p
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m EN 15662
Method" AOAC 2007. 01 Method
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![BioComma Copure Quechers-1 BioComma Copure Quechers-1](./BioComma-Copure-Quechers-1.jpg) |
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CT > Quechers
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re more SPE Restek Quechers : > PIC Gallery > courtesy of GOOGLE [ SEARCH ] PIcs > PDF LINKs
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> a Hi-TECH Resource for - Analytical Chemists ! CT-Chromatography > PIC Gallery > via these>PDF LINKs > Good IDEAS : Gadjets
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![arrow2 arrow2](./arrow2_18.jpg)
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FlipHTML5 Bookcase Library |
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THIS SITE (-m5) > “Child” pages
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some of Our Other Main OEM Suppliers !
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NOW use TAWK
from ~31Mar24+ but AI limitations ! > & U must PAY Extra 4 ! ? > but at least > Be-a-Ware ! . . . to install Tawke.to !
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some of Our “KEY “ Products
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11-2022+ HTM > FlipHTML5 a ”select” Shortcut chromtech11-current-m5 ( -updateCT11-m5 )
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but TRY MS-BING ~ AI > Very Good ! > “ Boolean” in comparison ! |
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