Quechers-Fast Simple Sample Prep for Multiresidue Pesticide

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Save Time and Money with QuEChERS
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• Ready-to-use extraction and dSPE tubes, no glassware required.
• Preweighed adsorbents for dSPE cleanup.
• Convenient, method-specific internal and QC standards.
Quick, Easy, Cheap, Effective, Rugged, and Safe, the QuEChERS (“catchers”)
method is a fast, simple, and effective alternative to conventional sample
prep for multiresidue pesticide analysis. QuEChERS is based on work done
by the U.S. 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 that they worked with routinely. They had been using the
modified Luke extraction method, which is highly effective and rugged, but
is solvent, labor, and glassware intensive, leading to a relatively high cost per
sample. In contrast, QuEChERS employs a very short shake-extraction step,
making it faster and less labor intensive. Solid phase extraction cleanup of
extracts from other methods also had been effective, but the complex matrices
the investigators were dealing with required multiple individual cartridges to
remove the many classes of interferences, which added significant cost and
complexity to the process. To reduce costs and speed up sample preparation, they developed a novel dispersive solid phase extrac-
tion (dSPE) technique, which effectively removes sugars, lipids, organic acids, sterols, proteins, pigments and excess water, but is far
simpler and less expensive than conventional methods (Table I).
Using QuEChERS, samples are prepared in three simple steps. As shown on the following page, samples are first homogenized,
then extracted and partitioned with an organic solvent and salt solution, with the extracts finally cleaned using the dSPE technique.
Using the dSPE approach, the quantity and type of sorbents can easily be optimized for different 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. Validation and proficiency data for the QuEChERS
method are available for a wide variety of pesticides in several common food matrices at
Restek Q-sep™ products make QuEChERS even simpler. All extraction salts, adsorbents, and sample tubes are included—no special-
ized equipment or glassware is required. The dSPE centrifuge tube format, available in 2 mL and 15 mL sizes, contains magnesium
sulfate (to partition water from organic solvent) and PSA adsorbent (to remove sugars and fatty acids), with or without graphitized
carbon (to remove pigments and sterols) or C18 (to remove nonpolar interferences). Custom products are available by request. If
you are frustrated with the time and expense of your current pesticide sample cleanup procedure, we suggest you try this simple,
economical new method.
Try QuEChERS risk-free today!
Call 1-814-353-1300 or 1-800-356-1688 to request a
free sample pack of Q-sep™ QuEChERS tubes.
Mini-Luke or Modified Savings with
Luke Method QuEChERS QuEChERS
Estimated time to process 6 samples (min) 120 30 4x faster
Solvent used (mL) 60-90 10 6-9x less solvent
Chlorinated waste (mL) 20-30 0 Safer, cheaper, greener
Glassware/specialized equipment capacity for 200 mL, quartz wool, none Ready-to-use
funnel, water bath, or evaporator
Table I: Prepare samples more quickly, easily, and cost-effectively with QuEChERS.