本文關鍵詞： 氮摻雜碳點 水熱法 蜂蜜 聚丙烯酰胺 水性聚氨酯 5-氧代-3 5-二氫-2H-噻唑[3 2-a]吡啶-7-羧酸 熒光檢測Au(Ⅲ) 谷胱甘肽 生物成像 熒光復合薄膜　出處：《南京大學》2015年博士論文　論文類型：學位論文

【摘要】：碳量子點,簡稱碳點,是一類小尺寸并且具有熒光特性的新型碳基納米材料。由于其低生物毒性及環(huán)境友好性、良好的熒光性能、優(yōu)異的分散性和化學穩(wěn)定性、優(yōu)異的抗光漂白性、易修飾性和低成本等特點在生物成像與生命標記、分析檢測、催化和光電子器件等領域有著廣泛的應用前景。雖然關于碳點合成和應用的報道絡繹不絕,但目前碳點仍存在著諸如熒光效率偏低、主要熒光發(fā)射波長多在藍光、缺乏調控手段和應用研究不深入等亟待解決的問題。本論文針對這些問題以蜂蜜和氨水、聚丙烯酰胺、水性聚氨酯等為碳源,利用水熱法設計制備了一系列新型高性能的氮摻雜碳點,通過改變反應條件或碳源組成來調節(jié)所制備碳點的性質(包括尺寸、溶解性和發(fā)光波長等),并將碳點應用于生命分析、生物成像和熒光薄膜等領域,主要包含以下四個方面的工作：(1)以天然蜂蜜為原料,在外加氨水的條件下,采用水熱法一步制備出粒徑在5nm左右,在365nm紫外燈照射下發(fā)射藍光的氮摻雜碳點,并發(fā)現(xiàn)氮元素的摻雜能夠提高碳點的熒光效率。該碳點可以構建熒光淬滅/恢復("off-on")探針用以檢測Au(Ⅲ)和谷胱甘肽。研究發(fā)現(xiàn)Au(Ⅲ)對制得的碳點具有選擇性淬滅并形成Au(Ⅲ)修飾的碳點團簇,而Au(Ⅲ)修飾的碳點團簇的熒光可以被谷胱甘肽等巰基生物分子特異性恢復。這一新型方法可用于檢測不同氧環(huán)境下細胞內谷胱甘肽的含量。(2)進一步以本體含氮的聚丙烯酰胺為碳源,采用水熱法一步制得了熒光效率大于10%的氮摻雜碳點,通過控制水熱反應的時間(24、72和96小時)可以獲得不同粒徑(5、20和50nm)的熒光碳納米粒子。通過透射電鏡、動態(tài)光散射、紅外、紫外、熒光光譜等手段對得到的熒光碳納米粒子的形貌、結構和熒光性質進行了表征。獲得的碳納米粒子可以應用于快速細胞成像,1小時即可觀察到熒光信號。另外,研究發(fā)現(xiàn)熒光碳納米粒子的尺寸與其進入細胞的能力相關,20 nm的粒子胞吞效果最好。(3)以水性聚氨酯乳液為原料,通過水熱法一步制得可分別在水相和有機相溶解的碳點,兩種碳點表面所含的官能團不同導致其溶解性的差異。水相碳點具有良好的熒光性能(熒光效率大于20%)和低生物毒性并可以應用于多色細胞成像；有機相碳點可均勻分散于多種有機溶劑,由此可進一步應用于熒光薄膜材料的制備。研究還發(fā)現(xiàn),通過選擇不同的水性聚氨酯軟段,可以調控水相和有機相碳點的產(chǎn)率；同時通過選擇不同種類的二異氰酸酯可以將獲得碳點的發(fā)光由藍光調控至藍綠光。(4)為了進一步提高材料的熒光效率,以檸檬酸和巰基乙胺為原料進行水熱反應,結果得到了熒光效率大于90%的小分子5-氧代-3,5-二氫-2H-噻唑[3,2-a]吡啶-7-羧酸(TPCA)。通過質譜、核磁、熒光光譜等手段表征了其結構并研究了其熒光性質。
[Abstract]:Carbon quantum dots, or carbon dots, are a new type of carbon based nanomaterials with small size and fluorescence properties. Due to their low biotoxicity and environmental friendliness, good fluorescence properties, excellent dispersion and chemical stability, Excellent photobleaching resistance, easy modification and low cost are widely used in the fields of biological imaging and life marking, analytical detection, catalysis and optoelectronic devices. However, there are still some problems in carbon spots, such as low fluorescence efficiency, the main emission wavelengths of fluorescence are blue light, lack of regulation and application research, etc. In this paper, honey and ammonia, polyacrylamide, and so on, are needed to solve these problems. A series of high performance nitrogen-doped carbon spots were prepared by hydrothermal method. The properties of the prepared carbon points (including size) were adjusted by changing the reaction conditions or the composition of carbon sources. Solubility and luminescence wavelength, and the application of carbon spots in the fields of life analysis, biological imaging and fluorescent film, mainly includes the following four aspects of work: 1) using natural honey as raw material, under the condition of added ammonia water, The nitrogen-doped carbon spots with the diameter of about 5 nm and the emission of blue light under the irradiation of 365nm ultraviolet lamp were prepared by one step hydrothermal method. It was also found that nitrogen doping can improve the fluorescence efficiency of carbon points, which can be used to construct fluorescence quenching / recovery ("off-on") probes for the detection of Au( 鈪，

本文編號：1527212