College of Chemistry and Chemical Engineering, Xinyang Normal University, 237# Chang An Road, Xinyang, 464000, Henan, China.
School of Chemistry and Chemical Technology, Shanghai Jiaotong University, Shanghai, 200240, China.
Anal Bioanal Chem. 2020 Feb;412(4):915-922. doi: 10.1007/s00216-019-02314-y. Epub 2020 Jan 3.
A tetrahedral DNA probe can effectively overcome the steric effects of a single-stranded probe to obtain well-controlled density and minimize nonspecific adsorption. Herein, a highly sensitive electrochemical biosensor is fabricated for determination of protein using a tetrahedral DNA probe and rolling circle amplification (RCA). N- and P-co-doped graphene (NP-rGO) is prepared, and AuNPs are then electrodeposited on it for DNA probe immobilization. Benefitting from the synergistic effects of the excellent electrical conductivity of NP-rGO, the stability of the tetrahedral DNA probe and the signal amplification of RCA, the biosensor achieves a low limit of 3.53 × 10 M for thrombin and a wide linear range from 1 × 10 to 1 × 10 M. This study provides a sensitive and effective method for the detection of protein in peripheral biofluids, and paves the way for future clinical diagnostics and treatment of disease. Graphical abstract.
一种四面体形 DNA 探针可以有效地克服单链探针的空间位阻，从而获得良好控制的密度并最小化非特异性吸附。在此，通过四面体 DNA 探针和滚环扩增（RCA）构建了一种用于测定蛋白质的高灵敏度电化学生物传感器。制备了 N 和 P 共掺杂石墨烯（NP-rGO），然后在其上电沉积 AuNPs 以固定 DNA 探针。得益于 NP-rGO 的优异导电性、四面体 DNA 探针的稳定性以及 RCA 的信号放大作用，该生物传感器对凝血酶的检测限低至 3.53×10-10 M，线性范围从 1×10-8 M 到 1×10-6 M。本研究为检测外周生物流体中的蛋白质提供了一种灵敏有效的方法，并为未来的临床诊断和疾病治疗铺平了道路。
