基于纳米银催化银沉积的核酸适配体传感器研究

Study on aptamer sense based on nanosilver catalytic silver deposition

文章以酶标板为分析平台,丝网印刷芯片电极为检测装置,构建电化学核酸适配体传感器。将生物素修饰的核酸适配体固定至链霉亲和素包裹的酶标板中,以巯基修饰的核酸适配体功能化的纳米银作为探针。通过三明治型的夹心反应后,加入银增强溶液,利用纳米银催化银沉积反应,在孔板中形成了大量的银沉积物。随着酸溶解生成的银沉积物后,插入印刷芯片电极,采用方波阳极溶出伏安法对释放出的银离子进行测定。银的电化学溶出峰与PDGF-BB的浓度相关,从而实现对PDGF-BB的定量测定。分析方法对PDGF-BB的测定结果良好,线性范围为3.12～200 ng/m L,检测限为1.23 ng/m L,且特异性良好。

In this paper,the electrode plate of ELISA is used as the analysis platform,and the electrode of screen printing chip is used as the detection device,to construct the electrochemical aptamer sensor.The biotin-modified aptamer is immobilized on streptavidin-coated microtiter plate and the aptamer-modified aptamer-functionalized nanosilver is used as a probe.The sandwich-type sandwich reaction by adding silver enhanced solution,the use of nano-silver catalytic silver deposition reaction in the orifice plate formed a lot of silver deposits.With the dissolution of silver generated by the acid deposition,insert the printed chip electrode,using square anodic stripping voltammetry to measure the release of silver ions.The electrochemical dissolution peak of silver is correlated with the concentration of PDGF-BB,so as to achieve the quantitative determination of PDGF-BB.The analytical method is good for the determination of PDGF-BB,with a linear range of 3.12 to 200 ng·mL-1 and a detection limit of 1.23 ng·mL-1 with good specificity.