以一步迴流合成法調控多顏色功能性奈米碳點

Abstract

奈米碳點是一種新穎的螢光奈米材料，因為具有低成本、高光穩定性、生物相容性佳和汙染性低的特性。但是一般奈米碳點的製備方法只產生一種顏色的螢光。此研究主要以一步合成的加熱迴流法製備不同放光顏色的螢光奈米碳點，藉由調控反應物溶液內氫氧化鈉的含量，則可產生具有藍色、綠色和黃色螢光奈米碳點。我們利用螢光分析法中的內濾鏡效應作為偵測原理，並設計不同種類的內濾鏡效應之偵測方法，將其分別應用於三種螢光奈米碳點，包含直接偵測、金屬奈米粒子的間接偵測和酵素反應的間接偵測，則可以檢測不同的分析物。以咖啡因、三聚氰胺和撲滅松作為目標分析物，分別應用於藍色、綠色和黃色的螢光奈米碳點，並結合三種內濾鏡效應的偵測策略。我們結合簡單製備奈米碳點的方法和內濾鏡效應的原理，則利用不同反應條件的加熱迴流法可以產生不同顏色的螢光奈米碳點，並且結合不同種類內濾鏡效應之偵測，即可設計具有功能性且靈敏度高的奈米碳點。

Carbon dots are admirable fluorescent nanomaterials due to their low cost, high photostability, excellent biocompatibility, and being environment friendly. Most conventional carbon dot fabrication approaches produce single-colored fluorescent material in the preparation process, different methods are therefore required to synthesize distinct carbon dots for specific applications. In this study, carbon dots carrying different emission colors are prepared through a one step refluxing process. The emission of these materials can be well tuned by sodium hydroxide content in the precursor solution. The produced carbon dots are used as sensing probes based on spectrofluorometric inner filter effect for target molecules detection. Three sensing categories that combine carbon dots and inner filter effect are demonstrated, including direct, metal nanoparticle-assisted, and enzymatic reaction supported detection. Caffeine, melamine and fenitrothion are selected as targets to demonstrate the strategies, respectively. These multi functional carbon dots based sensors achieve comparable sensitivity toward analytes with a much more convenient preparation route.