Potent antimicrobial and antibiofilm activities of bacteriogenically synthesized gold-silver nanoparticles against pathogenic bacteria and their physiochemical characterizations.
The objective of this study was to develop a bimetallic nanoparticle with enhanced antibacterial activity that would improve the therapeutic efficacy against bacterial biofilms. Bimetallic gold-silver nanoparticles were bacteriogenically synthesized using γ-proteobacterium, Shewanella oneidensis MR-1. The antibacterial activities of gold-silver nanoparticles were assessed on the planktonic and biofilm phases of individual and mixed multi-cultures of pathogenic Gram negative (Escherichia coli and Pseudomonas aeruginosa) and Gram positive bacteria (Enterococcus faecalis and Staphylococcus aureus), respectively. The minimum inhibitory concentration of gold-silver nanoparticles was 30-50 µM than that of other nanoparticles (>100 µM) for the tested bacteria. Interestingly, gold-silver nanoparticles were more effective in inhibiting bacterial biofilm formation at 10 µM concentration. Both scanning and transmission electron microscopy results further accounted the impact of gold-silver nanoparticles on biocompatibility and bactericidal effect that the small size and bio-organic materials covering on gold-silver nanoparticles improves the internalization and thus caused bacterial inactivation. Thus, bacteriogenically synthesized gold-silver nanoparticles appear to be a promising nanoantibiotic for overcoming the bacterial resistance in the established bacterial biofilms.
School of Chemical Engineering, Yeungnam University, Gyeongsan, Republic of Korea.
Mohankandhasamy
M
Ramasamy
School of Chemical Engineering, Yeungnam University, Gyeongsan, Republic of Korea.
Jin-Hyung
JH
Lee
School of Chemical Engineering, Yeungnam University, Gyeongsan, Republic of Korea jtlee@ynu.ac.kr.
Jintae
J
Lee
D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000138:chemical synthesis; D018407:Bacterial Physiological Phenomena / Q000187:drug effects*; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D001688:Biological Products / Q000008:administration & dosage / Q000737:chemistry; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006046:Gold / Q000008:administration & dosage / Q000737:chemistry; D053768:Metal Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D020592:Shewanella / Q000737:chemistry*; D012834:Silver / Q000008:administration & dosage* / Q000737:chemistry*
D000900:Anti-Bacterial Agents; D001688:Biological Products; D012834:Silver; D006046:Gold
Au–Ag NPs; Biological synthesis; Shewanella oneidensis; antibacterial; antibiofilm; bimetallic nanoparticles; electron microscope