Quick extraction kit adapted to a procedure of detecting pesticide residues in agricultural products and a method of obtaining a primary test liquid from an agricultural sample by the quick extraction kit
View Patent ↗The present invention provides a quick extraction kit adapted to a procedure of detecting pesticide residues in agricultural products and a method of obtaining a primary test liquid from an agricultural sample by the quick extraction kit. The quick extraction kit comprises a pipe, a first powder mixture layer and a second powder mixture layer. The method of taking primary test liquid is performed as follows. First, obtaining fragments of the agricultural sample. Second, adding an extraction solvent into the fragments of the agricultural sample to obtain a sample solution. Third, adding the sample solution into the pipe. Finally, driving the sample solution to export from the pipe to become the primary test liquid. The quick extraction kit and the method solve the problem of being unable to quickly obtain the result of detecting pesticide residues.
1. A quick extraction kit for use in extracting pesticide residues from a homogenized sample with a solvent and subsequently cleaning those extracted pesticide residues for analysis, comprising:
a pipe having an output port located at the bottom of the pipe and an input port located at the top of the pipe for receiving a sample solution obtained by shaking a mixture of the homogenized sample and the solvent;
a first powder mixture layer filled in the pipe, being capable of absorbing most of water of the sample solution and buffering a pH value of the sample solution, but not pesticide residues contained in the sample solution, when the sample solution flows through the first powder mixture layer; and
a second powder mixture layer filled in the pipe and between the first powder mixture layer and the output port, and being capable of absorbing the rest of water of the sample solution and impurities interfering with the analysis, but not the pesticide residues, when the sample solution flows through the second powder mixture layer so as to export from the output port a cleaned extract containing the pesticide residues ready for the analysis.
2. The quick extraction kit of claim 1 , wherein a density of the first powder mixture layer in the pipe is 0.7 to 1.3 g/cm 3 .
3. The quick extraction kit of claim 1 , wherein a porosity of the first powder mixture layer in the pipe is 35 to 70%.
4. The quick extraction kit of claim 1 , wherein the first powder mixture layer has components, comprising anhydrous magnesium sulfate powder for absorbing said most of water of the sample solution.
5. The quick extraction kit of claim 4 , wherein the second powder mixture layer comprises anhydrous magnesium sulfate powder less than that in the first powder mixture layer, for absorbing the rest of water of the sample solution.
6. The quick extraction kit of claim 5 , wherein the second powder mixture layer further comprises primary secondary amine powder, and graphitized carbon black powder for absorbing the impurities.
7. A method for extracting pesticide residues from an agricultural sample and subsequently cleaning those extracted pesticide residues for analysis, comprising:
homogenizing the agricultural sample;
shaking the homogenized agricultural sample with a solvent to obtain a sample solution;
adding the sample solution into said pipe of the quick extraction kit of claim 1 ; and
driving the sample solution in the pipe to flow through the first powder mixture layer and the second powder mixture layer in sequence to export from the output port of the pipe a cleaned extract containing the pesticide residues ready for the analysis.
8. The method of claim 7 , wherein a flow rate of the sample solution is controlled in a range of about 0.01 to 0.2 mL/sec.
9. The method of claim 7 , wherein the solvent comprises acetonitrile.
10. The method of claim 7 , wherein a density of the first powder mixture layer in the pipe is 0.7 to 1.3 g/cm 3 .
11. The method of claim 7 , wherein a porosity of the first powder mixture layer in the pipe is 35 to 70%.
12. The method of claim 7 , wherein the first powder mixture layer comprises anhydrous magnesium sulfate powder for absorbing said most of water of the sample solution.
13. The method of claim 12 , wherein the second powder mixture layer comprises anhydrous magnesium sulfate powder less than that in the first powder mixture layer, for absorbing the rest of water of the sample solution.
14. The method of claim 13 , wherein the second powder mixture layer further comprises primary secondary amine powder, and graphitized carbon black powder for absorbing the impurities.
15. The quick extraction kit of claim 1 , further comprising:
a first filter pad disposed above the first powder mixture layer for filtering out insoluble dregs from the sample solution; and
a second filter pad disposed underneath the second powder mixture layer for filtering out insoluble dregs from the second power mixture layer.
16. The quick extraction kit of claim 1 , further comprising a piston rod for driving the sample solution in the pipe to flow through the first powder mixture layer and the second powder mixture layer in sequence to discharge the cleaned extract.
17. The quick extraction kit of claim 1 , further comprising an injection tube that includes a tube for receiving the sample solution, and a piston rod for driving the sample solution in the tube to flow through the first powder mixture layer and the second powder mixture layer in sequence to discharge the cleaned extract.