Preparation And Application Of A Molecularly Imprinted Material Of The Azo Dye Named Chrysoidine

Chrysoidine is one of the azo dyes used mainly for basic textiles, leather products and wood stain products. However, as the chrysoidine dyeing so more easily and bleaching harder than other water-soluble orange dye such as sunset yellow, tartrazine and the low cost, it is used illegally in various food samples including the bean products, yellow croaker and chilli products. According to the United states Institute of Healthy, the healthy and safety database of chemical display that ingestion, inhalation and skin exposure to this substance may lead to poisoning. What's more, the illegal using of chrysoidine as additive in the food has seriously harmed the healthy of consumers. It is necessary to establish a sensitivity and high selective analytical technique with efficient sample pretreatment for determination of chrysoidine in foods.In this paper, by combining surface molecular imprinting technique with the sol-gel process, chrysoidine was used as template, silica gel as support material, 3-aminopropyltriethoxysilane as functional monomer, and tetraethoxysilicane as cross-linker, a novel basic orange ? molecularly imprinted polymer with good selectivity and sensitivity was prepared. With a series of optimization experiments, the optimum conditions of synthesis for this imprinted polymer were found. And this imprinted polymer was evaluated through adsorption experiments including static adsorption test, kinetic adsorption test and selective adsorption test, and characterized by Fourier transform infrared. The results indicated that the imprinted polymer exhibited fast binding kinetics, high selective ability and good adsorption capacity for chrysoidine.A determination method for chrysoidine in food was developed with the prepared polymer as a selective enrichment sorbent in an online solid phase extraction coupled with high-performance liquid chromatography. Besides in this research the parameters affecting the procedure including the pH of loading solvent, loading flow rate and the eluting time were optimized. Under the optimum conditions, the enrichment factor was 279, and the detection limit (S/N=3) was 6 ng L-1.The linear plots with r2>0.99 were achieved over a range of 0.04-40 ?g L-1 and the peak area precision (RSD) for nine parallel determinations was below 6.32%.At last in order to evaluate the applicability of this method, oil bean curd, yellow croaker and paprika, determined to be free of chrysoidine, were spiked with three levels of chrysoidine (20 ?g kg-1?40 ?g kg-1?80 ?g kg-1) and analyzed after simple pretreatment. Good recoveries of these samples were achieved ranging from 89.3% to 97.6%, which proved this new method was usefulness applied to the detection of chrysoidine.