黄曲霉毒素分子印迹聚合物的制备及应用研究

发布时间：2018-07-15 19:23

【摘要】：黄曲霉毒素是一类结构相似的二氢呋喃香豆素代谢产物,它主要是由曲霉真菌如黄曲霉和寄生曲霉产生,并污染谷类作物如(玉米、花生和饲料),及其他产品(如杏仁、无花果和牛奶)。由于具有很强的毒性、致畸性和致突变性,1993年世界卫生组织的癌症研究机构(WHO-IARC)将黄曲霉毒素B1(AFB1)划定为1类致癌物。为了保护人类的健康,建立一个简单、灵敏、低成本的方法用于痕量黄曲霉毒素的检测具有重要意义。本论文首先合成了一种对黄曲霉毒素具有高选择性识别能力的分子印迹聚合物。采用溶胶凝胶表面分子印迹方法,以5,7-二甲氧基香豆素(DMC)为假模板,负载型离子液体为功能单体和载体,四乙氧基硅烷(TEOS)为交联剂,合成了 DMC分子印迹聚合物。通过傅里叶红外光谱(FT-IR)、扫描电镜、吸附实验对分子印迹聚合物进行了表征。可知印迹聚合物不仅成功合成,而且传质速率较快。其次,将分子印迹聚合物作为固相萃取柱的填充材料,与高效液相色谱联用。在最优条件下,黄曲霉毒素B_1、B_2、G_1、G_2的线性相关系数为R20.9937,方法检出限(S/N=3)为0.03-0.09 μg L-1之间,RSD(n=9)9.7%。对分子印迹-固相萃取柱(MIP-SPE)进行选择性实验,研究表明,此柱对黄曲霉毒素的选择性吸附要远远高于赭曲霉毒素A和杂色曲霉毒素,6种黄曲霉毒素的竞争吸附表明,此柱对黄曲霉毒素B_1、B_2、G_1、G_2的吸附要高于黄曲霉毒素M1、M2。最后,为了验证实验所建立方法的实用性,对玉米、花生和饲料中的黄曲霉毒素进行了加标回收实验,结果表明,在低含量(10μg kg-1)时,黄曲霉毒素B1的回收率为77.8%-106.4%(RSD7.7%),黄曲霉毒素B2的回收率为34.0%-98.9%(RSD9.3%),黄曲霉毒素G1的回收率为44.3%-89.8%(RSD7.3%),黄曲霉毒素G2的回收率为24.3%-63.6%(RSD8.9%)。与免疫亲和柱相比,分子印迹-固相萃取柱中色谱图中杂质峰较少,对黄曲霉毒素B1具有较好的选择性。由于样品中黄曲霉毒素的种类较多和毒性很强,为充分利用分子印迹-固相萃取柱的优势,可以用于食品中黄曲霉毒素(B_1、B_2、G_1、G_2)的检测。总体考虑,分子印迹-固相萃取柱成本低,实验操作简单,对黄曲霉毒素的分离富集效果较好。因此分子印迹-固相萃取柱对于食品中黄曲霉毒素(B_1、B_2、G_1、G_2)的检测有一定的适用性。
[Abstract]:Aflatoxin is a similar class of dihydrofurancoumarin metabolites produced mainly by aspergillus fungi such as Aspergillus flavus and parasitic Aspergillus sp., and contaminates cereals such as (corn, peanuts and fodder), as well as other products such as almonds, Fig and milk Because of its strong toxicity, teratogenicity and mutagenicity, aflatoxin B1 (AFB1) was classified as a class 1 carcinogen by the World Health Organization's Cancer Research Institute (WHO-IARC) in 1993. In order to protect human health, it is important to establish a simple, sensitive and low-cost method for the detection of trace aflatoxin. In this paper, we first synthesized a molecularly imprinted polymer with high selective recognition ability for aflatoxin. DMC molecularly imprinted polymers were synthesized by using sol-gel surface molecular imprinting method using 5-dimethoxy-coumarin (DMC) as false template, supported ionic liquids as functional monomer and carrier, and tetraethoxysilane (TEOS) as crosslinking agent. The molecularly imprinted polymers were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy and adsorption experiments. It can be seen that imprinted polymers are not only successfully synthesized, but also have a fast mass transfer rate. Secondly, the molecularly imprinted polymer was used as the filling material of solid phase extraction column and coupled with high performance liquid chromatography. Under the optimum conditions, the linear correlation coefficient of aflatoxin B _ (1) B _ (2) / T _ (2) G _ (2) was R20.9937, and the detection limit (S / N ~ (3) was 0.03-0.09 渭 g 路L ~ (-1), RSD (n ~ (9) = 9.7). The selective adsorption of aflatoxin on MIP-SPE column was studied. The results showed that the selective adsorption of aflatoxin was much higher than that of ochratoxin A and six aflatoxins. The adsorption of aflatoxin B _ (1) B _ (2) to aflatoxin B _ (1) C _ (2) was higher than that of aflatoxin M _ (1) / M _ (2). Finally, in order to verify the practicability of the method established in the experiment, the aflatoxin in corn, peanut and fodder was reclaimed. The results showed that at low content (10 渭 g kg-1), aflatoxin in corn, peanut and feed were recovered. The recoveries of aflatoxin B1, aflatoxin B2, aflatoxin G1 and aflatoxin G2 were 77.8% -106.4% (RSD 7.7%), 34.0-98.9% (RSD9.3%), 44.3% -89.8% (RSD7.3%) and 24.3-63.6% (RSD8.9%), respectively. Compared with the immuno-affinity column, the chromatogram of molecularly imprinted solid phase extraction column showed less impurity peaks and better selectivity for aflatoxin B1. In order to make full use of the advantages of molecularly imprinted solid phase extraction (SPE) column, aflatoxin can be used for the determination of aflatoxin in food. On the whole, the cost of molecularly imprinted solid phase extraction column is low, the experimental operation is simple, and the separation and enrichment of aflatoxin is better. Therefore, the molecularly imprinted solid phase extraction column can be used for the detection of aflatoxin in food.
【学位授予单位】：天津科技大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TS207.4;O631.3

【相似文献】