论文部分内容阅读
分别以柠檬酸和蛋氨酸为碳源和功能化前驱体,采用高温热解法制备新型蛋氨酸功能化石墨烯量子点(Met-GQDs)。Met-GQDs具有石墨烯类似的晶体结构,平均粒径为3 nm,氮、硫元素成功掺入到石墨烯量子点中。相对于仅由柠檬酸制备的石墨烯量子点,Met-GQDs表现出更好的荧光强度和光稳定性,表明蛋氨酸功能化基团的引入能明显改善石墨烯量子点的光学性质。基于Met-GQDs荧光对环境pH的灵敏响应,建立了检测pH的分析方法。当pH在1~14之间,Met-GQDs的荧光强度随p H的增加而线性增大。方法在灵敏度和pH响应范围方面优于文献报道的光学传感器,已成功应用于环境水样中pH快速检测和细胞成像。
The new methionine-functionalized grapheme quantum dots (Met-GQDs) were prepared by high temperature pyrolysis using citric acid and methionine as carbon sources and functionalized precursors respectively. Met-GQDs have a graphene-like crystal structure with an average particle size of 3 nm. Nitrogen and sulfur elements are successfully incorporated into the quantum dots of graphene. Met-GQDs showed better fluorescence intensity and photostability than graphene quantum dots prepared from citric acid, indicating that the introduction of methionine functional groups can improve the optical properties of graphene quantum dots. Based on the sensitive response of the fluorescence of Met-GQDs to the pH of the environment, an analytical method for the determination of pH was established. When the pH is between 1 and 14, the fluorescence intensity of Met-GQDs increases linearly with the increase of p H. The method is superior to the optical sensors reported in the literature in terms of sensitivity and pH response range and has been successfully applied to rapid pH detection and cell imaging in environmental water samples.