Herein, we present a label-free, resettable, multi-readout, and fluorescent logic system by employing bovine serum albumin (BSA) and 3-mercaptopropionic (MPA) co-stabilized gold nanoclusters (BSA/MPA–AuNCs) as a basic work unit. Small chemical molecules including Fe2+, Fe3+, H2O2 and H+/OH− are selected as the inputs to induce the change in fluorescence intensity of BSA/MPA–AuNCs through a non-radiative electron transfer mechanism. Using this novel strategy, a versatile logic system capable of performing elementary logic operations (NAND, NOR, and IMPLICATION) and integrative logic operations (NAND + NOR) can be successfully constructed. More importantly, the logic operations can be also performed on a solid surface in which BSA/MPA–AuNCs are complexed with polyelectrolytes and are coated on a glass slide. We envision that the current work will bring new ideas in establishing chemical logic gates in both liquid media and solid forms.
Fuyuan Zhang,Jing Wang,Weihua Liu,Qingge Shi,Hangrui Liu,Yaxin Sang,Xianghong Wang
The presence of psychotropic drugs (PDs) in aquatic ecosystems represents an increasing environmental problem, posing a serious threat to human health and aquatic organisms. Lateral flow immunoassays (LFIA) have been widely used in the detection of PD contaminants. However, maintaining signaling tag reporting activity and achieving LFIA's multi-readout capability remain significant challenges to meeting a range of detection scenarios. Here, a rapid multifunctional LFIA has been developed for detecting diazepam (DAP), an emerging environmental and food safety PD contaminant, in lake water and fish samples. Copper hexacyanoferrate nanoparticles doped with Au and Pt (AuPt@Cu-HCF) were designed and manufactured as a multi-signal reporter with exceptional photothermal conversion efficiency and peroxidase-like enzymatic activity. This study integrates the colorimetric, photothermal, catalytic colorimetric, and catalytic photothermal effects of the AuPt@Cu-HCF nanozyme to form a “four-in-one” multi-readout LFIA. The multifunctional detection approach achieved four different detection signal outputs for DAP, with detection limits of 0.82 ng/mL, 12.82 pg/mL, 12.26 pg/mL, and 4.43 pg/mL for the basic colorimetric, photothermal, catalytic colorimetric, and colorimetric photothermal readout modes, respectively. This quadruplex-functional LFIA offers four different options with varying sensitivities and detection ranges, suitable for various application scenarios. It also allows multiple verifications for a single sample, enhancing detection accuracy.
危险品化学品经营许可证（带存储）