基于金纳米粒子组装体的手性传感器及应用

Chirality originated from assemblied superstructure, demonstrates good specificity and sensitivity. In this study,gold nanoprtices in different diameters will be controllably synthesized and quantitatively functionalized with antibody or antigen. Various types of assemblied structures were fabricated through the specific reaction between antigen and antibody.The collective chirality of products is determined using circular dichroism (CD)and the assemblied superstucture will be characteized . The assemblied nano-stucture with strong collective chriality are applied to develop chrial nanosensor. The origin of collective chirality will be illustrated by computer simulation. The antibody and antigen against mycotoxin will be used in this system. Afer optimization of reaction conditions,the relationship of CD response and concentration of mycotoxin would be investigated to develop a universal chirality detection platform.With quantitative modification of gold nanoparticles and effective pretreatment of samples, the developed chiral sensor could be applied in mycotoxin analysis of milk products.The studies above provide a new approach in food analysis and could signi?cantly promote the technical development of novel sensor.

基于自组装超分子的手性信号区别于其他光学检测信号，具有较好的特异性和较高的灵敏度。本研究拟对纳米粒子进行抗原、抗体修饰，通过特异的抗原抗体反应，可控形成不同类型的纳米组装体。采用圆二色光谱对组装体的手性光学性质进行表征，筛选具有强簇手性信号的组装体。基于组装结构，开展计算机数学模型的构建，从探索纳米粒子组装体手性产生的内在因素。 以具有强手性性质的纳米组装体作为目标组装产物，采用生物毒素的抗原/抗体修饰纳米粒子，进一步优化纳米粒子表面抗原、抗体修饰条件，提高目标纳米组装体的产率。 通过改变体系中生物毒素的浓度，考察组装体系手性信号变化的情况，确立手性信号和生物毒素的线性关系，构建基于手性信号的纳米生物传感器，并将其应用于乳制品中生物毒素的检测，为新型超灵敏生物传感器的构建以及检测新原理的发展提供科学依据。

本项目以贵金属纳米粒子（金、银）、上转换纳米粒子（UCNP）以及荧光量子点材料为对象，通过在其表面进行定量、定位修饰，制备特异性纳米探针，利用核酸杂交、抗原抗体亲和反应，实现了纳米基元的自组装。利用生物分子的亲和/杂交特性调节纳米粒子之间的距离和耦合强度，实现了圆二色光谱吸收、上转换发光信号以及荧光信号的可控调制。. 将制备的纳米组装结构与生物体系相孵育，实现了细胞内和活体内生命物质的实时检测，检测灵敏度达到单拷贝。项目执行过程中发表 Nat Comm 1篇，J Am Chem Soc论文1篇，Adv Mater 2篇，Nano Lett 1篇，Adv Funct Mater 4篇，Small 4篇， 获得国家发明专利5项，该研究为新型超敏生物传感器的构建及等离子手性检测新原理的发展提供了科学依据。