Li Jing, Hu Bingtao, Zhang Yanxin, Xu Qin, Li Hongbo
School of Chemistry and Chemical Engineering, Yancheng Institute of Technology, Yancheng, 224051, P. R. China.
Institute of Innovation Materials and Energy, Yangzhou University, Yangzhou, 225002, P. R. China.
Anal Bioanal Chem. 2025 Mar 25. doi: 10.1007/s00216-025-05848-6.
Dual-signal mode sensors that can self-validate detection results have attracted considerable interest; however, creating those with superior overall performance still presents significant challenges. Herein, we develop a unique photoelectrochemical (PEC) and photothermal (PT) dual-mode biosensor targeting microRNA-221 (miRNA-221), built on an innovative entropy-driven DNA circuit (EDC). The zinc oxide nanorods (ZnO NRs) serve as PEC beacons, while copper sulfide nanoparticles (CuS NPs) function as photocurrent inhibitors and PT beacons, both biofunctionalized with DNAs before being assembled through partial base pairing. When target miRNA-221 is present, the EDC activates and releases output DNAs that open partially hybridized strands anchored to ZnO NRs via competitive assembly. This process liberates CuS-DNA1 and restores the suppressed photocurrent. The results demonstrate linear relationships between photocurrent/temperature increment and the logarithm of target concentration across ranges of 1.0 fmol L-50.0 pmol L (limit of detection (LOD): 0.35 fmol L) and 5.0×10 fmol L-5.0 nmol L (LOD: 1.22×10 fmol L), respectively. Compared to conventional EDCs, our optimally designed EDC not only doubles the output DNA yield but also significantly enhances sensor sensitivity. Additionally, the target-triggered EDC amplification strategy effectively minimizes reversibility in each reaction step, preserves base sequence integrity, boosts efficiency, and demonstrates strong thermal stability and selectivity, thereby increasing the specificity of the dual-mode biosensor. Furthermore, ZnO NR photoelectric beacons fabricated via electrodeposition greatly improve the stability and controllability of the photoelectrode while avoiding lengthy modification processes. Overall, this thoughtfully engineered dual-mode biosensor offers numerous advantages, including a wide linear range, excellent stability, high reproducibility, and user-friendly operation. Specifically, this signal-on type dual-signal output biosensor enables self-confirmation of detection results, significantly enhancing both accuracy and reliability.
能够自我验证检测结果的双信号模式传感器引起了广泛关注；然而，制造出具有卓越整体性能的此类传感器仍面临重大挑战。在此，我们基于创新的熵驱动DNA电路（EDC），开发了一种针对微小RNA - 221（miRNA - 221）的独特光电化学（PEC）和光热（PT）双模式生物传感器。氧化锌纳米棒（ZnO NRs）用作PEC信标，而硫化铜纳米颗粒（CuS NPs）用作光电流抑制剂和PT信标，二者在通过部分碱基配对组装之前均用DNA进行了生物功能化修饰。当存在目标miRNA - 221时，EDC被激活并释放输出DNA，这些输出DNA通过竞争性组装打开锚定在ZnO NRs上的部分杂交链。此过程释放出CuS - DNA1并恢复被抑制的光电流。结果表明，在1.0 fmol L至50.0 pmol L（检测限（LOD）：0.35 fmol L）和5.0×10 fmol L至5.0 nmol L（LOD：1.22×10 fmol L）范围内，光电流/温度增量与目标浓度的对数之间分别呈现线性关系。与传统的EDC相比，我们优化设计的EDC不仅使输出DNA产量翻倍，还显著提高了传感器的灵敏度。此外，目标触发的EDC扩增策略有效地最小化了每个反应步骤中的可逆性，保留了碱基序列完整性，提高了效率，并表现出强大的热稳定性和选择性，从而提高了双模式生物传感器的特异性。此外，通过电沉积制备的ZnO NR光电信标极大地提高了光电极的稳定性和可控性，同时避免了冗长的修饰过程。总体而言，这种精心设计的双模式生物传感器具有众多优点，包括宽线性范围、出色的稳定性、高重现性和用户友好的操作。具体而言，这种信号开启型双信号输出生物传感器能够自我确认检测结果，显著提高了准确性和可靠性。
