HPLC Determination of SudanⅠ-Ⅳ in Food with Molecularly Imprinted Solid Phase Extraction

The molecularly imprinted polymer of Sudan red was synthesized with Sudan Ⅰ as template molecule and methacrylic acid as functional monomer, and it was used to extract Sudan Ⅰ-Ⅳ from food as adsorbent in solid phase extraction column. The sample was extracted with acetonitrile, and the extract obtained were purified on MIP-SPE column. Sudan Ⅰ-Ⅳ adsorbed on the imprinted polymer were eluted with ethanol-n-hexane (1+1) mixture, which were collected and used for HPLC determination. It was found that the imprinted polymer had good affinity and excellent selectivity for SudanⅠ-Ⅳ. Linearity range for the determination was found between 0.5-15 mg·L-1, and detection limit (3S/N) was 4 μg·kg-1. Using chili powder and chili sauce as matrixes, test for recovery was made at 3 concentration levels, values of recovery found were in the range of 70.3%-85.5% with RSD′s (n=5) less than 6.0%.