Key Laboratory of Flexible Electronics (KLOFE) and Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM), Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing, 211816, China.
Henan Key Laboratory of Chemo/Biosensing and Chemometrics, Henan Joint International Research Laboratory of Chemo/Biosensing and Early Diagnosis of Major Diseases, Henan Engineering Center of New Energy Battery Materials, Henan D&A Engineering Center of Advanced Battery Materials, School of Chemistry and Chemical Engineering, Shangqiu Normal University, Shangqiu, 476000, China.
Talanta. 2019 Dec 1;205:120132. doi: 10.1016/j.talanta.2019.120132. Epub 2019 Jul 13.
The present work constructs a sequentially triggered nanoswitch (STN) for sequential detection of Cr, PO (PPi) and alkaline phosphatase (ALP) depending on polythymine (T40) templated fluorescent Cu nanoparticles (Cu NPs). A significant phenomenon is that Cr can only causing 5% QE of fluorescent Cu NPs synthesized by lower than 500 μM Cu, but the fluorescence of the Cu NPs synthesized by more than 500 μM Cu can be quenched up to 90% QE by the same concentration of Cr. Then the quenched fluorescence of CuNP-Cr complex provides a sensing platform for PPi due to the strong binding between Cr and PPi, resulting in dissociation of Cr from the surface of Cu NPs and the recovery of fluorescence emission. Further ALP hydrolysis of PPi disrupts Cr-PPi assemble and Cr is released to interact with Cu NPs, which induces fluorescence quenching again. Thus, sequentially detection of Cr (LOD, 0.03 μM), PPi (LOD, 0.005 μM) and ALP (LOD, 0.125 mU/mL) was successfully implemented with high sensitivity and selectivity. The sensor is also successfully used for Cr, PPi and ALP assays in the human serum. Additionally, the sensitive "on-off-on-off" sensing behavior of the Cu NPs allow three chemical inputs (Cr, PPi and ALP) to construct a logic gate.
本工作构建了一种顺序触发的纳米开关（STN），用于基于多聚胸腺嘧啶（T40）模板的荧光 Cu 纳米粒子（Cu NPs）顺序检测 Cr、PO（PPi）和碱性磷酸酶（ALP）。一个显著的现象是，Cr 只能引起低于 500 μM Cu 合成的荧光 Cu NPs 的 5%QE，但相同浓度的 Cr 可以猝灭超过 500 μM Cu 合成的 Cu NPs 的荧光高达 90%QE。然后，由于 Cr 和 PPi 之间的强结合，猝灭的 CuNP-Cr 复合物的荧光为 PPi 提供了一个传感平台，导致 Cr 从 Cu NPs 表面解离，恢复荧光发射。进一步的 PPi 水解 ALP 破坏了 Cr-PPi 组装，Cr 被释放出来与 Cu NPs 相互作用，再次引起荧光猝灭。因此，成功地实现了对 Cr（LOD，0.03 μM）、PPi（LOD，0.005 μM）和 ALP（LOD，0.125 mU/mL）的顺序检测，具有高灵敏度和选择性。该传感器还成功地用于人血清中 Cr、PPi 和 ALP 的测定。此外，Cu NPs 的灵敏“开-关-开-关”传感行为允许三个化学输入（Cr、PPi 和 ALP）构建逻辑门。
