Wu Yongli, Ye Zhuoxin, Chen Yuxuan, Zhang Yan, Liu Ruiyan, Ma Pinyi, Song Daqian
College of Chemistry, Jilin Province Research Center for Engineering and Technology of Spectral Analytical Instruments, Jilin University, 2699 Qianjin Street, Changchun 130012, China.
ACS Sens. 2025 Aug 22;10(8):6231-6240. doi: 10.1021/acssensors.5c02005. Epub 2025 Jul 30.
Perovskite quantum dots (PQDs), particularly CsPbBr QDs, are highly promising electrochemiluminescent (ECL) materials due to their excellent optical properties. However, the key challenge in developing PQD materials for practical applications lies in balancing the contradiction between their intrinsic instability in aqueous environments and ECL efficiency. To address this challenge, we employed DNA nanosheets as templates to direct the self-assembly of CsPbBr QDs, into highly ordered two-dimensional superlattices. This strategy enhances electronic coupling effects through long-range ordered arrangement, enabling rapid charge-carrier transport. High-resolution XPS confirmed charge transfer between CsPbBr QDs, while AFM characterization reveals that the nanosheets possess a periodic structure with a spacing of 63.4 nm. Compared to unassembled CsPbBr QDs, the ECL intensity of CsPbBr/DNA NSs increased by 2.5-fold, with a respectably high ECL efficiency of 65.5%. Remarkably, they retain 83.3% of the initial ECL intensity retained after 10 days in aqueous conditions, significantly surpassing the stability of unprotected CsPbBr. Furthermore, these nanosheets were successfully applied in a ratiometric ECL biosensor for miRNA-221 detection, achieving a detection limit of 6.05 aM. This study presents a novel strategy that simultaneously addresses the aqueous instability and enhances the ECL efficiency of CsPbBr QDs, significantly advancing their applications in biosensing.
钙钛矿量子点（PQDs），尤其是CsPbBr量子点，因其优异的光学性能而成为极具潜力的电化学发光（ECL）材料。然而，开发用于实际应用的PQD材料的关键挑战在于平衡其在水性环境中的固有不稳定性与ECL效率之间的矛盾。为应对这一挑战，我们采用DNA纳米片作为模板来指导CsPbBr量子点自组装成高度有序的二维超晶格。这种策略通过长程有序排列增强了电子耦合效应，实现了快速的电荷载流子传输。高分辨率XPS证实了CsPbBr量子点之间的电荷转移，而原子力显微镜（AFM）表征表明纳米片具有间距为63.4 nm的周期性结构。与未组装的CsPbBr量子点相比，CsPbBr/DNA纳米片的ECL强度提高了2.5倍，ECL效率高达65.5%。值得注意的是，在水性条件下放置10天后，它们仍保留了初始ECL强度的83.3%，显著超过了未保护的CsPbBr的稳定性。此外，这些纳米片成功应用于用于检测miRNA-221的比率型ECL生物传感器，检测限达到6.05 aM。本研究提出了一种新颖的策略，同时解决了CsPbBr量子点在水中的不稳定性问题并提高了其ECL效率，显著推动了它们在生物传感中的应用。
