QuEChERS method overview
As people’s life quality improves, the emphasis on food safety continues to increase. Some foods contain agricultural and veterinary drug residues, which have a large adverse impact on public health and environmental pollution. At this stage, there are many detection methods for drug residues in food. QuEChERS can be effectively applied to many types of multi-residue samples, and the detection results are very accurate and reliable.
Introduction to QuEChERS principles
The function of the QuEChERS extraction and purification kit is to remove the interfering matrix from the sample in two steps. The first step is to transfer the pesticide residues in the sample from water to the added organic phase (acetonitrile) by using MgSO4 and buffer salts.
In the second step, fillers containing MgSO4, PSA, C18, and GCB are added respectively according to the matrix, MgSO4 is used to remove excess water, PSA can remove fatty acids and sugars, GCB can remove pigments and sterols, C18 ensures pesticides are not soluble Lipid layer produced in fatty fruits and vegetables (sample> 1% fat).
PS: Before extraction, at least 10g of the sample should be taken for homogenization; if the sample is dried fruit, a small amount of water must be added before homogenization; the sample is added to a 50ml centrifuge tube for the first step of extraction; The second step is completed by drawing the sample supernatant into a 2ml or 15ml centrifuge tube.
Operation process
As a method for the preparation of drug residues, it has the characteristics of simplicity, accuracy, reliability, economy, and safety. The application process is mainly divided into three steps. In the first step, an organic solvent is used to extract the high-humidity sample, and the salt is added to promote the separation of water and solvent. In the second step, after shaking and centrifuging the mixed system, part of the organic phase is mixed with the adsorbent and purified by dispersing solid phase extraction; finally, after centrifuging the mixture, the supernatant is directly analyzed or solvent exchanged.
Application advantages
Compared with the previous pesticide residue analysis methods, the QuEChERS method has many advantages, as follows:
First, the recovery rate is higher, and the recovery rate can be more than 85% for pesticides that are more volatile and difficult to detect;
Secondly, the amount is higher, and the detection of 10-20 pre-weighed samples can be completed within 30-40 minutes. During the detection process, the operator’s own technical level is not high, and each sample can use the same vessel repeatedly, simple and convenient;
Thirdly, it is the simultaneous removal and purification of fatty acids and other organic acids in the food;
Fourthly, the method is more economical, and the equipment used in sample preparation requires fewer types, just the crusher, centrifuge, and balance.
HAWACH and its products
Over the years, HAWACH has won the praise of customers at home and abroad for its consistent high-quality, professional-level technical services and excellent reputation. HAWACH provides high quality of extraction and purification kits with centrifugal tubes of 50ml, 2ml, and 15ml. The centrifugal tubes are featuring fewer impurities dissolve in organic solvents, good sealing, no leakage of organic solvents; corrosion resistance, high speed centrifugal resistance and do not interfere with pesticide residue detection. Welcome to visit hawach.com to learn more.
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