基于新型纳米酶构建适体传感器用于食品中AFB_(1)的检测

Construction of an aptasensor based on a novel nanoenzyme for the detection of AFB_(1) in food

黄曲霉青素B_(1)(AFB_(1))是天然食品中最为常见的一类污染物,其毒性和致癌性也最强.实验合成了具有类过氧化氢酶性质的金属有机骨架材料Mn MOF纳米酶,经高温炭化后得到Mn MOF-C,通过掺杂铂纳米颗粒得到复合材料Pt NPs@Mn MOF-C,发现其催化能力可进一步增强.将该复合材料作为标记物用于制备AFB_(1)适体传感器,利用适体的高度亲和力与高特异性,使其与AFB_(1)发生特异性结合从电极表面解离下来,导致Pt NPs@Mn MOF-C催化过氧化氢产生的电流信号减小,从而实现食品中AFB_(1)的定量检测.在0.001~100 ng/mL范围内,随着目标物AFB_(1)质量浓度的增大,响应信号逐渐降低.研究构建的适体传感器灵敏度高、耗费时间短,可用于真实大米样品中AFB_(1)的检测,展现出良好的应用前景.

Aflatoxin B_(1)(AFB_(1))is the most common class of contaminants in natural foods,and it is also the most toxic and carcinogenic.In this work,metal organic framework nanoenzyme(Mn MOF)with catalase-like properties were synthesized.The Mn MOF-C was obtained after high-temperature carbonization,and the composite Pt NPs@Mn MOF-C was obtained by doped platinum nanoparticles,which was found that its catalytic capacity could be further enhanced.The composite was used as a marker to prepare the AFB_(1) aptamer sensor.The aptamer with high affinity and high specificity can be specifically bind to AFB_(1) and dissociates from the electrode surface,resulting in a reduced current signal catalyzed by Pt NPs@Mn MOF-C,thus achieving quantitative detection of AFB_(1) in food.In the range of 0.001 to 100 ng/mL,the response signal gradually decreased as the mass concentration of the target AFB_(1) increased.The aptasensor constructed in this work has high sensitivity and short time consuming,and can be used for AFB_(1) detection in real rice samples,showing good application prospects.