A novel bifunctional molecularly imprinted polymer for determination of Congo red in food

A novel bifunctional molecularly imprinted polymer was synthesized in an aqueous system with Congo red as template, beta-cyclodextrin-maleic anhydride (beta-CD-MA) and [2-(methacryloyloxy) ethyl] trimethylammonium chloride (DMC) as co-functional monomers and N, N-methylenebisacryl amide (MBA) as cross-linking agent, respectively. MIP was used as selective sorbent for the solid-phase extraction (SPE) of Congo red from food. And the elution was determined by HPLC. The mean recovery was 84.2-105.2%, the RSD <= 1.2%, the repeatability was 1.1-3.8%. The LOD and LOQ were 0.07 and 0.23 mu g kg(-1), respectively. The evaluation of validation data verified that the MIP has high selectivity and recovery, and it can be applied for the selective extraction and determination of Congo red in food.