College of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212100, P. R. China.
College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211800, P. R. China.
Anal Chem. 2022 Mar 15;94(10):4303-4310. doi: 10.1021/acs.analchem.1c04971. Epub 2022 Mar 1.
In this work, a new electrochemiluminescence (ECL) platform was constructed for detecting the prostate cancer marker microRNA-141 (miRNA-141) on a constant resistor-integrated closed bipolar electrode (BPE). It consisted of two reservoirs and a constant resistor, and both ends were connected to the anode of the driving electrode and the cathode of BPE. The cathode of BPE was modified with boron nitride quantum dots (BNQDs), and the anode reservoir was the Ru(bpy)/TPrA system. After introducing a certain amount of hairpin DNA 3 (H3) and ferrocene-labeled single-stranded DNA (Fc-ssDNA) on the surface of the BNQDs, the ECL emission signal of the BNQDs was difficult to be observed by the naked eye, while Ru(bpy) emitted a strong and visible ECL signal. In the presence of the target, bipedal DNA assembled by catalytic hairpin assembly (CHA) took away the Fc-ssDNA and the ECL intensity of the BNQDs was enlarged, and as the concentration of miRNA-141 increased to the cutoff value, yellow-green light was visible by the naked eye. Meanwhile, the red emission signal of Ru(bpy)/TPrA became weakened. Thus, an ultrasensitive "color switch" ECL biosensor for detection of miRNA-141 was constructed and endowed with a wide linear range from 10 to 10 M and a detection limit of 10 M (S/N = 3). This study provides the potential for investigating portable devices in the detection of low-concentration nucleic acids.
在这项工作中，我们构建了一种新的电化学发光（ECL）平台，用于在恒阻集成闭双极电极（BPE）上检测前列腺癌标志物 microRNA-141（miRNA-141）。它由两个储液器和一个恒阻器组成，两端分别连接到驱动电极的阳极和 BPE 的阴极。BPE 的阴极用氮化硼量子点（BNQDs）修饰，阳极储液器为[Ru（bpy）]（PF）/TPrA 体系。在 BNQDs 表面引入一定量的发夹 DNA 3（H3）和二茂铁标记的单链 DNA（Fc-ssDNA）后，BNQDs 的 ECL 发射信号难以用肉眼观察，而[Ru（bpy）]（PF）发出强而可见的 ECL 信号。在存在靶标的情况下，由催化发夹组装（CHA）组装的双足 DNA 带走了 Fc-ssDNA，BNQDs 的 ECL 强度增大，并且随着 miRNA-141 浓度增加到截止值，肉眼可见黄绿色光。同时，[Ru（bpy）]（PF）/TPrA 的红色发射信号减弱。因此，构建了一种超灵敏的“颜色开关”ECL 生物传感器用于检测 miRNA-141，并具有从 10 到 10 M 的宽线性范围和 10 M（S/N = 3）的检测限。这项研究为研究用于检测低浓度核酸的便携式设备提供了潜力。
