Bacterial synthesis of anisotropic gold nanoparticles

作者：Islam M. Ahmady, Javad B. M. Parambath, Elsiddig A. E. Elsheikh, Gwangmin Kim, Changseok Han, Alejandro Pérez‐García, Ahmed A. Mohamed · 发表于：Applied Microbiology and Biotechnology · 年份：2025 · DOI：10.1007/s00253-025-13438-w · 被引用次数：13 · 研究领域：Nanoparticles: synthesis and applications、Advanced Nanomaterials in Catalysis、Graphene and Nanomaterials Applications

Abstract Pseudomonas aeruginosa was used to synthesize anisotropic gold nanoparticles from the unusually reducible aryldiazonium gold (III) salt of the chemical formula [HOOC-4-C 6 H 4 N≡N]AuCl 4 (abbreviated as DS-AuCl 4 ). We investigated the effect of bacterial cell density, temperature, and pH on the AuNP synthesis. The bacterial cell density of 6.0 × 10 8 CFU/mL successfully reduced 0.5 mM DS-AuCl 4 salt to AuNPs after incubation at 37 °C (24 h), 42 °C (24 h), and 25 °C (48 h). Transmission electron microscopy (TEM) images revealed the formation of spherical, triangle, star, hexagon, and truncated triangular morphologies for the AuNPs synthesized using P. aeruginosa bacteria. The average size of AuNPs synthesized at 25 °C (48 h), 37 °C (24 h), and 42 °C (24 h) was 39.0 ± 9.1 nm, 26.0 ± 8.1 nm, and 36.7 ± 7.7 nm, respectively. The average size of AuNPs synthesized at pH 3.7, 7.0, and 12.7 was 36.7 ± 7.7 nm, 14.7 ± 3.8 nm, and 7.3 ± 2.5 nm, respectively, with the average size decreasing at a pH of 12.7. The reduction of the DS-AuCl 4 salt was confirmed using X-ray photoelectron spectroscopy (XPS). The significant peaks for C1s, Au4f doublet, N1s, and O1s are centered at 285, 84–88, 400, and 532 eV. The ability of inactivated bacteria (autoclave-dead and mechanically lysed bacteria), peptidoglycan, and lipopolysaccharides to reduce the DS-AuCl 4 salt to AuNPs was also investigated. Anisotropic AuNPs were synthesized using inactivated bacteria and peptidoglycan but not using...