【摘要】 目的建立一种高选择性的、非标记、操作简单的检测Hg²⁺的荧光分析方法。方法利用紫外可见吸收光谱法,在260 nm波长下测吸光度,对DNA进行定量分析,准确测定实验所用DNA片段的浓度;利用荧光光谱法,在激发波长为445 nm,扫描范围为455～650 nm下,检测单碱基T/T错配的双链DNA探针加入核黄素和Hg²⁺前后,核黄素的荧光信号的变化。结果单碱基错配的双链DNA能有效检测10～200 nM Hg²⁺。该体系的荧光比率（F/F₀）与Hg²⁺浓度具有良好的线性关系,其线性方程为F/F₀=0.000 9C（nmol/L）+0.004 9,相关系数r²=0.993 0,检出限为3.3 nM （S/N=3）。相对标准偏差（RSD）小于1.37%;样品回收率为100.8%～103.3%。结论该方法可用于环境水样中Hg²⁺的测定。更多还原

【Abstract】 Purposes—To establish a highly selective, label-free, simple-operation fluorescence detection method for detecting Hg²⁺. Methods—The absorbance was measured with ultraviolet-visible absorption spectroscopy at a wavelength of 260 nm for quantitative analysis of DNA and accurate determination of the concentration of the DNA fragments used in the experiment. Fluorescence spectroscopy was used to detect the changes in fluorescence signal of riboflavin at excitation wavelength of 445 nm and scanning range of 455～650 nm before and after the addition of riboflavin and Hg²⁺ to single-base T/T mismatched double-stranded DNA probes. Result—Single-base mismatched double stranded DNA can effectively detect 10～200 nM Hg²⁺. The fluorescence ratio（F/F₀） of the system has a good linear relationship with the Hg²⁺ concentration. The linear equation is F/F₀=0.000 9C（nmol/L）+0.004 9, the correlation coefficient r² was equal to 0.993 0 and the detection limit was 3.3 nM（S/N=3）. The relative standard deviation（RSD） was less than 1.37%, and the recovery ranged from 100.8% to 103.3%. Conclusion—This method can be used for the determination of Hg²⁺ in water samples in bad environment.更多还原