Yellow-emitting Au/Ag bimetallic nanoclusters with high photostability for detection of folic acid

In this work, a simple one-pot preparation protocol is presented for synthesis of adenosine monophosphate-stabilized bimetallic gold/silver nanoclusters (AMP-Au/Ag NCs). These yellow-emitting NCs (lambda(em) = 560 nm) with quantum yield of 7.3% show great kinetic stability and photostability as well. Besides the detailed size, composition, and structural characterizations, the pH-dependent aggregation induced emission was identified. Moreover, their possible utilization as folic acid (FA) biosensor was also investigated in liquid phase and for design of paper-based quick test. Based on the detailed analysis of the fluorescence quenching data, the limit of detection (0.109 mu M) and dynamic range (0.15-2.5 mu M) of FA were calculated and the thermodynamic nature, as well as the proposed mechanism of the fluorescence quenching process via an interesting etching reaction of alloy clusters, was also interpreted. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The study presents a simple one-pot preparation protocol for the synthesis of AMP-Au/Ag NCs, which show potential applications as biosensors and in rapid testing. Detailed analysis revealed the detection limit and dynamic range of the NCs as folate sensors, and proposed a mechanism for the fluorescence quenching process.