Department of Basic Chemistry, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian Province, 350108, China.
Department of Pharmaceutical Analysis, School of Pharmacy, Fujian Medical University, Fuzhou, Fujian Province, 350108, China.
Talanta. 2020 Jan 15;207:120257. doi: 10.1016/j.talanta.2019.120257. Epub 2019 Aug 14.
A label-free electrochemical biosensor based on the triplex DNA-templated Ag/Pt bimetallic nanoclusters (triplex-Ag/PtNCs) and locked nucleic acid (LNA) modified X-shaped DNA probe was developed for the detection of single-nucleotide variant (SNV) related to β-thalassemia. Firstly, using triplex DNA as template, a site-specific and homogeneous Ag/PtNCs was prepared, which can effectively catalyze the 3,3,5,5-tetramethylbenzidine-HO system and thus be employed as a signal reporter in the field of electrochemical biosensor. Secondly, the LNA modified X-shaped probes were assembled on gold electrode surface, which can only be dissociated in the presence of target, leading to the hybridization with triplex-Ag/PtNCs and significant increase of current signal. In this way, the detection limit for SNV of β-thalassemia was 0.8 fM with variant allele frequency (VAF) as low as 0.0001%.
基于三链 DNA 模板的 Ag/Pt 双金属纳米团簇（triplex-Ag/PtNCs）和锁核酸（LNA）修饰的 X 型 DNA 探针的无标记电化学生物传感器被开发用于检测与β-地中海贫血相关的单核苷酸变异（SNV）。首先，使用三链 DNA 作为模板，制备了一种具有特异性和均一性的 Ag/PtNCs，它可以有效地催化 3,3,5,5-四甲基联苯胺-HO 体系，因此可以作为电化学生物传感器领域的信号报告分子。其次，LNA 修饰的 X 型探针被组装在金电极表面，只有在存在靶标时才会解离，导致与 triplex-Ag/PtNCs 的杂交和电流信号的显著增加。通过这种方式，β-地中海贫血的 SNV 的检测限为 0.8 fM，变异等位基因频率（VAF）低至 0.0001%。
