聚多巴胺磁分子印迹材料制备及其在食用油中黄曲霉毒素B富集中的应用

Preparation of polydopamine magnetic molecularly imprinted polymers for enrichment of aflatoxin B in edible oil

中文关键词:  磁分子印迹材料  5,7-二甲氧基香豆素  黄曲霉毒素B  多巴胺  食用油  一步法

英文关键词:magnetic molecularly imprinted polymers  5,7-dimethoxycoumarin  aflatoxin B  dopamine  edible oil  one-step synthesis

中文摘要:

      目的 建立了基于聚多巴胺磁性分子印迹聚合物吸附富集食用油中黄曲霉毒素B的方法。方法 以多巴胺为功能单体和交联剂, 5,7-二甲氧基香豆素为模拟模板分子, 一步法在Fe3O4 NPs表面制备磁分子印迹聚合物。采用透射电子显微镜和红外光谱仪对该分子印迹材料形态和结构进行表征, 研究了其对两种黄曲霉毒素B吸附性能。最终以该印迹材料作为分散固相萃取剂, 对影响黄曲霉毒素B吸附的条件进行了优化。结果 该分子印迹材料对两种黄曲霉毒素B的吸附模式符合Langmuir理论, 对黄曲霉毒素B1和黄曲霉毒素B2最大吸附容量分别为0.460和0.047 mg/g。在最佳萃取条件[材料用量(10 mg)、溶液pH (7)、超声时间(5 min)和1 mL(解吸2次, 每次0.5 mL) 3%乙酸/乙腈作为解析液]下, 结合配有大体积流通池的超高效液相色谱-荧光检测法定量检测, 黄曲霉毒素B1和黄曲霉毒素B2浓度分别在0.005~0.500 ng/mL (r=0.9989)和0.001~0.100 ng/mL (r=0.9992)范围内与对应的峰面积呈现良好的线性相关性, 检出限分别为0.0024和0.00038 ng/mL, 食用油样品加标回收率为93.2%~104.0%, 相对标准偏差5.8%~7.7%, 且可重复使用至少7次。结论 该吸附富集方法具有快速、低廉、选择性高、稳定性好等特点, 适用于食用油中黄曲霉毒素B的前处理。

英文摘要:

      Objective To develop a method for the extraction and enrichment of aflatoxin B in edible oil by the specific magnetic molecularly imprinted polymers. Methods Using dopamine as a functional monomer and cross-linker, and 5,7-dimethoxycoumarin as the dummy template, the molecularly imprinted polymers were fabricated on the surface of ferroferric oxide nanoparticles by a one-pot method. The prepared molecularly imprinted polymers were characterized through a transmission electron microscopy and a Fourier transform infrared spectrometer. The adsorption properties towards two aflatoxin B were studied. The molecularly imprinted polymers were used as a sorbent for dispersive solid-phase extraction, the conditions affecting the adsorption of aflatoxin B were optimized. Results The adsorption properties of molecularly imprinted polymers to two aflatoxin B matched the Langmuir isotherm model, and the maximum adsorption capacities were 0.460 mg/g for aflatoxin B1 and 0.047 mg/g for aflatoxin B2. Under optimized conditions including molecularly imprinted polymers amount (10 mg), pH value 7, equilibrium time (5 min), and 1 mL (eluted twice, each 0.5 mL) 3% acetic acid/acetonitrile as desorption solvent, ultra performance liquid chromatography-fluorescence detection method with large volume flow cell was used for quantitative detection, the calibration plots were linear in the range of 0.005?0.500 ng/mL (r=0.9989) and 0.001?0.100 ng/mL (r=0.9992) with the limits of detection of 0.0024 and 0.00038 ng/mL for aflatoxin B1 and aflatoxin B2, respectively. The recoveries from spiked edible oil sample were 93.2%?104.0% with relative standard deviations of 5.8%?7.7%. And the molecularly imprinted polymers could be reused for 7 cycles. Conclusion The adsorption enrichment method has the characteristics of rapid, low cost, high selectivity and good stability, and is suitable for the pretreatment of aflatoxin B in edible oil.