Issue 19, 2024

Ligand-regulated catalytic activity in fluorescent gold nanoclusters

Abstract

Ligand engineering is crucial for tailoring the catalytic and fluorescence properties of gold nanoclusters (AuNCs). However, the mechanisms through which ligands synergistically affect these properties remain largely unexplored. Here we employed single-molecule fluorescence microscopy and ensemble fluorescence spectroscopy to investigate how water-soluble thiol ligands modulate the fluorescence and catalytic activities of AuNCs. Our findings reveal that small ligands, such as 3-mercaptopropionic acid (MPA), provide high catalytic activity, despite lacking fluorescence. Medium-sized ligands, like glutathione (GSH) and the lysine–cysteine–lysine (KCK) peptide, enhance fluorescence and maintain catalytic activity through their stable ligand structures and non-competitive mechanisms. Large protein ligands, such as bovine serum albumin (BSA), significantly increase fluorescence and catalytic activity by controlling their conformation to enhance substrate adsorption but experience reduced catalytic rates due to their competitive binding at high substrate concentrations. Additionally, pH levels influence these properties, with fluorescence intensity increasing under alkaline conditions and catalytic activity peaking in acidic environments for small and medium-sized ligand-AuNCs. For BSA-AuNCs, optimal activity is observed at neutral pH due to favorable protein conformation, where enhanced substrate adsorption has a more significant impact on the catalytic rate than merely exposing gold active sites. These insights into the ligand size and structure-dependent modulation of the catalytic and fluorescence properties of AuNCs lay a foundation for designing efficient fluorescent catalysts.

Graphical abstract: Ligand-regulated catalytic activity in fluorescent gold nanoclusters

Supplementary files

Article information

Article type
Research Article
Submitted
22 jul. 2024
Accepted
10 ago. 2024
First published
13 ago. 2024

Inorg. Chem. Front., 2024,11, 6396-6405

Ligand-regulated catalytic activity in fluorescent gold nanoclusters

W. Yang, S. Wang, X. Wei, Z. Feng, G. Qin, J. Mao, Z. Zhen, X. Miao, Y. Cheng, X. Wang, F. Huang and H. He, Inorg. Chem. Front., 2024, 11, 6396 DOI: 10.1039/D4QI01828A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements