Frontiers in Microbiology (Oct 2022)

One-step synthesized antimicrobial peptide-functionalized gold nanoclusters for selective imaging and killing of pathogenic bacteria

  • Yunqiu Shen,
  • Chaochuan Zheng,
  • Qiaoli Wu,
  • Qilong Wu,
  • Ming Jin,
  • Yayun Jiang,
  • Fuyuan Huang,
  • Yongliang Lou,
  • Laibao Zheng

DOI
https://doi.org/10.3389/fmicb.2022.1003359
Journal volume & issue
Vol. 13

Abstract

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The development of multifunctional nanomaterials with bacterial imaging and killing activities is of great importance for the rapid diagnosis and timely treatment of bacterial infections. Herein, peptide-functionalized gold nanoclusters (CWR11-AuNCs) with high-intensity red fluorescence were successfully synthesized via a one-step method using CWR11 as a template and by optimizing the ratio of CWR11 to HAuCl4, reaction time, pH, and temperature. The CWR11-AuNCs bound to bacteria and exhibited selective fluorescence microscopy imaging properties, which is expected to provide a feasible method for locating and imaging bacteria in complex in vivo environments. In addition, CWR11-AuNCs not only retained the antibacterial and bactericidal activities of CWR11 but also exhibited certain inhibitory or killing effects on gram-negative and gram-positive bacteria and biofilms. The MICs of CWR11-AuNCs against Escherichia coli and Staphylococcus aureus were 178 and 89 μg/ml, respectively. Surprisingly, cell viability in the CWR11-AuNC-treated group was greater than that in the CWR11-treated group, and the low cytotoxicity exhibited by the CWR11-AuNCs make them more promising for clinical applications.

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