Yuan Xinxin, Geng Wenchao, Ji Jiangying, Yan Zhiyi, Wei Jiarui, Wu Yongjun, Yang Ruiying
College of Public Health, Zhengzhou University, Zhengzhou 450001, China.
School of Chemical and Printing Dyeing Engineering, Henan University of Engineering, Zhengzhou 451191, China.
ACS Sens. 2025 Feb 28;10(2):1270-1279. doi: 10.1021/acssensors.4c03180. Epub 2025 Jan 31.
Circular RNAs (circRNAs), as a class of noncoding RNA molecules with a circular structure exhibit high stability and spatiotemporal-specific expression, making them ideal cancer biomarkers for liquid biopsy. Herein, a new photoelectrochemical (PEC) biosensor for a highly sensitive circRNA assay in the whole blood of lung cancer patients was designed based on CRISPR/Cas13a-programmed Cu nanoclusters (Cu NCs) and a -scheme covalent organic framework/silver sulfide (T-COF/AgS) composite. This -scheme T-COF/AgS composite accelerates electron transfer and produces an excellent initial photocurrent. When CRISPR/Cas13a precisely targets circRNA, it nonspecifically cleaves the triple-helix molecular structure to release DNA fragments (C'/C"). After the C'/C" opens the DNA hairpin probe (HP) modified on the electrode, hybridization chain reactions are performed to produce abundant AT-rich double-stranded DNA with the addition of H1 and H2 probes. Upon the incubation of Cu, Cu NCs are formed via the A-Cu-T bonds and can effectively quench the photocurrent of the -scheme T-COF/AgS due to the energy transfer process. This developed PEC biosensor for the circRNA assay shows a low limit of detection of 0.5 fM, and the reusability of DNA-modified magnetic beads (MB-DNA) reduces the detection cost. Moreover, the PEC biosensor can accurately quantify the circRNA level and distinguish the circRNA expression in whole blood from healthy controls and lung cancer patients, offering strong potential in clinical diagnosis.
环状RNA（circRNAs）作为一类具有环状结构的非编码RNA分子，具有高度稳定性和时空特异性表达，使其成为液体活检理想的癌症生物标志物。在此，基于CRISPR/Cas13a编程的铜纳米簇（Cu NCs）和一种 - 方案共价有机框架/硫化银（T - COF/AgS）复合材料，设计了一种用于肺癌患者全血中高灵敏度circRNA检测的新型光电化学（PEC）生物传感器。这种 - 方案T - COF/AgS复合材料加速电子转移并产生优异的初始光电流。当CRISPR/Cas13a精确靶向circRNA时，它会非特异性切割三螺旋分子结构以释放DNA片段（C'/C"）。C'/C"打开修饰在电极上的DNA发夹探针（HP）后，加入H1和H2探针进行杂交链式反应，产生大量富含AT的双链DNA。在铜存在下孵育时，通过A - Cu - T键形成Cu NCs，由于能量转移过程，其可有效淬灭 - 方案T - COF/AgS的光电流。这种开发的用于circRNA检测的PEC生物传感器检测限低至0.5 fM，DNA修饰磁珠（MB - DNA）的可重复使用性降低了检测成本。此外，该PEC生物传感器能够准确量化circRNA水平，并区分健康对照和肺癌患者全血中的circRNA表达，在临床诊断中具有强大潜力。
