基于磁性纳米粒子、氧化石墨烯及金属纳米簇的高选择性免标记生物传感器的构建及应用

Quantitative detection of tumor markers and environmental pollutants is of great importance for clinical diagnosis, environmental monitoring. In this project, based on the magnetic properties of magnetic nanoparticles (MNPs) and fluorescence quenching ability of graphene oxide (GO), combining with the fluorescence properties of copper nanoclusters (CuNPs), we aim to develop a novel label-free biosensor possessing low background, low-cost, high sensitivity and selectivity. First, DNA functionalized MNPs are used to capture the target, then GO and CuNPs based platform is employed for the detection of target molecules. The non-specific desorption of GO based sensor is effectively avoided by introducing MNPs in this design, which give the direct guidance for the practical application of GO. Meanwhile, the higher separation efficiency of MNPs provides a guarantee for the accurate detection of target. In addition, unlike other reported label-free amplification strategy, owing to the introduction of CuNPs and hybridization chain reaction, this method is non-toxic, fast and low-cost. Most importantly, it is potential for the wide application in the clinical diagnosis, environmental monitoring and other fields.

肿瘤标志物、环境污染物等的定量检测对临床诊断、环境监测具有非常重要的意义。本项目基于磁性纳米粒子的磁性能、氧化石墨烯的荧光猝灭性能，结合铜纳米簇的荧光性能，构建了一种低背景、低成本、高灵敏、高选择性的非标记型生物传感器。首先利用DNA功能化的磁性纳米探针识别和捕获靶分子，然后利用基于氧化石墨烯和铜纳米簇的检测平台对其进行检测。本项目中磁性纳米探针的引入有效避免了氧化石墨烯检测平台在实际样品检测时存在的非特异性吸附的问题，对氧化石墨烯的实际应用具有重要的指导作用。同时，磁性纳米粒子较高的分离效率，为后期靶分子的准确检测提供了保障。此外，与其它已报道的免标记放大策略相比，由于本方法以铜纳米簇为信号探针，且引入了杂交链式反应放大技术，因而具有无毒、快速、低成本等优势，有望被广泛应用于临床诊断、环境监测等领域。

疾病标志物、环境污染物等的定量检测对临床诊断、环境监测具有非常重要的意义。氧化石墨烯因具有荧光猝灭能力、生物相容性好等优势，在生物分析检测中得到了极大的关注。其中，基于氧化石墨烯和DNA作用力大小差异的非共价检测平台因具有成本低、背景低、毒性低等优势二备受青睐。然而，该检测平台仍然面临着很多的挑战：非特异性吸附问题、非标记型放大策略的建立。本项目利用磁性纳米离子的磁分离，有效解决了氧化石墨烯检测平台在实际样品检测时存在的非特异性吸附的问题。此外，基于氧化石墨烯的猝灭性能构建了多种低成本、高灵敏的检测平台，成功用于疾病标志物的检测。在本项目研究期间，发表SCI收录论文7篇。