基于适配体的荧光生物传感器对Hg^(2+)的检测技术研究

Research on the Detection Technique of Hg^(2+)Based on Aptamer Fluorescence Biosensor

工业迅速发展所带来的重金属污染,是目前威胁人类健康的重要环境问题之一。Hg^(2+)是一种毒性强且污染较为普遍的重金属离子,较低浓度Hg^(2+)就会对人体造成很大危害。基于核酸适配体错配结合Hg^(2+)的原理,以特异性双链核酸染料SYBR GreenⅠ为荧光指示探针,构建了新型的无标记核酸适配体荧光生物传感器,建立了一种高灵敏度、快速检测Hg^(2+)的方法,实现了Hg^(2+)高效检测。在优化条件下,传感器对Hg^(2+)的检测线性范围为10 nmol/L~1μmol/L,相关系数(r^(2))为0.99,检出限为1 nmol/L。5种干扰离子(Ca^(2+)、Fe^(2+)、Cu^(2+)、Ni^(2+)、Ag^(+))的存在不影响Hg^(2+)检测,表明该方法对Hg^(2+)检测具有较好的特异性。在自来水样的Hg^(2+)加标检测实验中,平均回收率达到95.8%,具备分析实际样品的能力。

With the rapid development of industry,the pollution of heavy metal has become one of the most serious environmental problems.Mercury is a heavy metal ion with strong toxicity and common pollution,which can cause harm to human body even with low concentration.Based on the principle of mismatched binding Hg^(2+)of nucleic acid aptamer,using the specific double-stranded fluorescent dye-SYBR GreenⅠas pointing probe,a novel label-free aptamer fluorescent biosensor was designed and developed.A high sensitivity,fast and convenient fluorescence detection method was developed to achieve efficient detection of Hg^(2+).Under the optimum conditions,a dynamic range of 10 nmol/L~1μmol/L(r^(2)=0.99)was obtained with a detection limit as low as 1 nmol/L.The presence of five interfering metal ions such as Ca^(2+),Fe^(2+),Cu^(2+),Ni^(2+)and Ag^(+)did not affect the detection of Hg^(2+),which indicated the high specificity for Hg^(2+)detection.The average recovery rate was 95.8%for Hg^(2+)-labeled detection in the experimental samples of tap water,showing the ability to be used for actual sample analysis.