Visible-light triggered self-breathing-like dual-photoelectrode internal-driven self-powered sensor: Metal-ligand charge transfer (MLCT) induced signal-off strategy for the microcystin-LR assay
Visible-light triggered self-breathing-like dual-photoelectrode internal-driven self-powered sensor: Metal-ligand charge transfer (MLCT) induced signal-off strategy for the microcystin-LR assay
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DOI：
10.1016/j.bios.2020.112414
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发表时间：
2020-10-01
影响因子：
12.6
通讯作者：
Sun, Jun
中科院分区：
文献类型：
--
作者：
Du, Xiaojiao;Zhang, Bing;Sun, Jun
Developing new self-powered sensors is highly demanded for smart portable electronic devices. Herein, a novel visible-light-driven self-powdered aptasensor with a metal-ligand charge transfer (MLCT)-induced signal-off strategy was established for microcystin-LR (MC-LR) sensing. The aptasensor was based on a self-breathinglike dual photoelectrode photocatalytic fuel cell (PFC) that was assembled with visible-light responsive ternary NG-TiO2-Ag and NG-BiOBr nanocomposites as photoelectrodes. The device did not require aeration or a membrane in a single-compartment cell. The self-powdered PFC system exhibited a greater power output than previously-reported ones that used only TiO2. The photo-triggered self-bias between the photoelectrodes generated electron transfer and a power output in the external circuit. A self-powered aptasensor for MC-LR was constructed using an MC-LR-binding aptamer as the recognition element. The results showed an unexpected sequential decrease in power output, followed by the capture of MC-LR, which is different from earlier signal-on strategies. The inhibited output of the PFC after MC-LR capture was controlled by an MLCT-induced signal-off mechanism, which was confirmed by the UV-Vis absorption and fluorescence emission spectra. Furthermore, the power output of the self-powdered sensor depended on the MC-LR concentration. When used for ultrasensitive trace MC-LR detection, the self-powdered sensor showed a linear relationship from 1 pM to 316 nM and a detection limit of 0.33 pM. This work provides theoretical guidance for sensing strategies using self-powdered sensors and offers a rational device design for cost-effective electricity generation from renewable resources.
