He commented that my Sample Pre-treatment by Solid-Phase Extraction is GOOD, but complained for a average of 15 $ on the SPE per sample.
Ok, here is another alternative for Sample Pre-treatment, I named it as dispersive solid-phase extraction.
(1 ) Extraction: Transfer 15 g of ample, accurately weighted, in 50-mL PS Centrifuge tube. Add 15-mL Glacial Acetic Acid-Acetonitrile (1:1), 6 g of anhydrous Mg2SO4, 1.5 anhydrous Na2SO4, then shake it mechanical 1 min, centrifuge the mixture for 5 min under 5000 r/min for further purify.
(2) Purification: Weight 0.1 g PSA，0.1 g C18，0.3 g of anhydrous Mg2SO4 into a 5-mL glass centrifuge tube, then pipet 2-mL of clear solution into the tube.Mixing the solution by using multi-function mixer whirlpool for 1 min, centrifuge the mixture for 1 min under 5000 r/min . Pipet 1-mL of the upper clear solution into 1 ml volumetric flask for the assay preparation.
To ensure the precision of the assay results, highly recommend the follow steps.
(3) Add the internal standard and protective agents: Put the 1 ml volumetric flask onto a Nitrogen blowing Instrument, blow with N2, concentrate the solution volume is less than 0.8-mL at room temp.Transfer an accurately weighted quantity 100 100 µL internal standard of TPP and 100-µL of protective agent’s mixture solution. Bring to the volume with Acetonitrile. Homogenize the solution on a vortex 5 min for GC-MS analysis.
Would you please update me if it works. Thanks.
Appreciate your comments.
Note:Working 200% well with the vegetable juices and fruit juices. For the Grains, Beans, Nuts, Seeds, please add more water and increase extraction time with vigorous mechanically shake, it also works.
