双荧光发射碳点的研制、发光机理及细胞微环境下H2O2的检测应用

Carbon dot is a promising material for biological fluorescent sensor due to its unique characteristic such as broad emission, good stability and superior biocompatibility. Based on the quenching effect of H2O2, carbon dots can be used as a fluorescent sensor for H2O2 detection in tumor cells, which have exorbitant H2O2 level. However, the slow responsibility, low sensitivity and low accuracy are the main problems of current H2O2 sensor, which strongly restrict its further application. Based on the previous research results, we have found the emission of carbon dot actually originate from several fluorescent centers. Thus the dual emission carbon dots can be obtained by adjusting the proportion of each part, while the surface induced emission can be easily quenched by microenvironment. Therefore, we propose to design a dual emissive carbon dot as fluorescent sensor for H2O2 detection due to the radiometric fluorescence change. Further investigation of carbon dots fluorescent mechanism and H2O2 quenching mechanism will be discussed to improve the effect of sensor, facilitating the fast responding and high resolution sensing aiming at H2O2. During this program, the fluorescent mechanism of carbon dot will be further revealed, and a new approach to H2O2 detection in cell will be provided.

碳量子点发光范围易调节，光稳定性好，生物相容性高，是作为生物荧光探针的优良材料。基于H2O2对其荧光的猝灭作用，可用作H2O2浓度异常的肿瘤细胞内微环境下的H2O2水平的检测。而当前的H2O2分子探针主要存在响应速度慢，灵敏度不高，易被干扰的问题，制约了其实际应用。我们前期研究发现，碳量子点的发光源于多个发光中心，而通过调节各部分比例可获得具有双重发光的荧光碳点，而其表面态发光易被微环境淬灭。因此本项目拟通过设计一种具有双波长发射的碳量子点荧光探针，利用其发射峰比例的变化实现对H2O2的检测。并通过研究碳量子点的荧光机理和H2O2的淬灭机理改善荧光探针效果，最终实现细胞内H2O2的快响应，高灵敏度的特异性检测。本项目进一步揭示了碳量子点的荧光机理，而且对细胞内H2O2检测提供了新的途径。

碳量子点作为一种新型纳米荧光材料，近年来在由于其出色的荧光性能而备受关注。通过该项目合成了具有高量子效率的荧光碳量子点，并完成了碳点对于H2O2的荧光检测。同时开发了具有长波长红色发光的碳点及纤维素膜复合物；以及Mn掺杂的荧光碳点用于可视化Fe3+检测试纸和单一体系污染物降解。研究了高浓度量子点掺杂聚合物分散液晶用于聚合物随机激光。这些结果对于研究制备抗固态猝灭的纳米荧光材料和荧光性能提升上具有普适性，在LED照明、传感器和显示器方面具有很大的应用潜力。