基于氮硼掺杂碳量子点荧光探针测定血清中多巴胺的含量

Determination of serum dopamine content based on fluorescence quenching probe of nitrogen-boron-doped carbon quantum dots

目的以氮硼掺杂碳量子点(nitrogen-boron-doped carbon quantum dots,N,B-CQDs)为荧光探针,建立一种测量血清中多巴胺(dopamine,DA)含量的方法。方法以柠檬酸钠为碳源,2-氨基-3-羟基吡啶为氮源,硼氢化钠为硼源,通过水热法制成水溶性较强的N,B-CQDs。采用透射电子显微镜(transmission electron microscope,TEM)、X射线光电子能谱技术(X-ray photoelectron spectroscopy,XPS)和傅里叶变换红外光谱仪(fourier transform infrared spectrometer,FTIR)对其进行了表征。在pH 9.0的碳酸钠-碳酸氢钠缓冲溶液中,DA和N,B-CQDs在40℃的恒温水浴锅中加热200 min,激发波长为354 nm,发射波长为420 nm,DA对N,B-CQDs荧光具有淬灭效应,可以实现DA的定量分析。结果在最佳实验条件下,DA对N,B-CQDs的荧光淬灭与DA的浓度在(5×10^(-6)~1.50×10^(-4))mol/L范围内呈良好线性关系,检出限为1.3×10^(-6)mol/L。该方法成功地应用于血清中DA的含量测定,回收率为99.24%~102.3%,相对标准偏差为1.8%~3.1%。结论基于N,B-CQDs荧光淬灭构建了一种应用于DA的分析检测的方法。该方法操作简单,灵敏度高,选择性好。

Objective To establish a method for measuring dopamine(DA)content in serum by nitrogen-boron-doped carbon quantum dots(N,B-CQDs)as a fluorescence probe.Methods N,B-CQDsb was prepared by hydrothermal method with sodium citrate as carbon source,2-amino-3-hydroxypyridine as nitrogen source,and sodium borohydride as boron source.Transmission electron microscope(TEM),X-ray photoelectron spectroscopy(XPS)and fourier transform infrared spectrometer(FTIR)were used to characterize N,B-CQDs.In pH 9.0 sodium carbonate-sodium bicarbonate buffer solution,DA and N,B-CQDs were heated in a constant temperature water bath at 40℃for 200 min,the excitation wave length was 354 nm and the emission wave length 420 nm.DA had quenching effect on fluorescence of N,B-CQDs,and the quantitative analysis of DA could be realized.Results Under optimal experimental conditions,the fluorescence quenching of N,B-CQDs by DA showed good linear relationships with the concentration of DA in the range of 5×10^(-6)mol/L-1.50×10^(-4)mol/L,with the detection limit of 1.3×10^(-6)mol/L.The method was successfully applied to determination of DA content in serum,and the recoveries were between 99.24%and 102.3%.The relative standard deviations were in the range of 1.8%-3.1%.Conclusion A method for DA analysis and detection based on fluorescence quenching of N,B-CQDs is constructed.And the proposed method is simple operation,higher sensitivity and better selectivity.