微波辅助快速制备氮掺杂碳点并用于铜的超灵敏检测

Microwave-assisted rapid preparation of N-doped carbon dots for ultra-sensitive detection of copper

以葡萄糖作为碳前驱体,2-甲基咪唑作为氮源掺杂,以微波辅助法一步制备表面含有咪唑基团和氨基的氮掺杂碳点(N-CDs),经过离心、过滤以及透析对所制备碳点进行提纯。采用高分辨透射电镜、红外、XRD、紫外和荧光等对其进行表征。结果显示,该碳点粒径均匀、荧光性能良好,且Cu^(2+)可对N-CDs选择性的猝灭,在0~5μmol/L浓度范围内,其荧光猝灭程度与Cu^(2+)的浓度呈现良好的线性关系,检出限为10 nmol/L。据此构建的荧光探针用于测定实际水样中的Cu^(2+),加标回收率为94.0%~98.5%。

Carbon dots(CDs)were rapidly fabricated via microwave-assisted method which used glucose and 2-mehylimidazole as the sources of carbon and nitrogen precursor.The purified CDs were obtained by centrifugation,filtration and dialysis.The results of the characterization made by HRTEM,FTIR,XRD,UV-vis and fluorescence spectra showed that the CDs have uniform size distribution,satisfactory water-solubility and stable fluorescence emission.Copper ions exhibited selective quenching effect on the fluorescence intensities of N-CDs.In the range of 0-5μmol/L,a good linear relationship can be obtained,and the detection limit was 10 nmol/L.Therefore,a highly selective and sensitive fluorescence probe for Cu^(2+) detection has been established,which was additionally applied in real water samples determination with the recoveries of 94.0%-98.5%.