Antibacterial effects of titanium embedded with silver nanoparticles based on electron-transfer-induced reactive oxygen species.
Although titanium embedded with silver nanoparticles (Ag-NPs@Ti) are suitable for biomedical implants because of the good cytocompatibility and antibacterial characteristics, the exact antibacterial mechanism is not well understood. In the present work, the antibacterial mechanisms of Ag-NPs@Ti prepared by plasma immersion ion implantation (PIII) are explored in details. The antibacterial effects of the Ag-NPs depend on the conductivity of the substrate revealing the importance of electron transfer in the antibacterial process. In addition, electron transfer between the Ag-NPs and titanium substrate produces bursts of reactive oxygen species (ROS) in both the bacteria cells and culture medium. ROS leads to bacteria death by inducing intracellular oxidation, membrane potential variation, and cellular contents release and the antibacterial ability of Ag-NPs@Ti is inhibited appreciably after adding ROS scavengers. Even though ROS signals are detected from osteoblasts cultured on Ag-NPs@Ti, the cell compatibility is not impaired. This electron-transfer-based antibacterial process which produces ROS provides insights into the design of biomaterials with both antibacterial properties and cytocompatibility.
Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
Guomin
G
Wang
Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
Weihong
W
Jin
Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
Abdul Mateen
AM
Qasim
Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
Ang
A
Gao
Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
Xiang
X
Peng
Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
Wan
W
Li
Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China; Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences; National Center for Nanoscience and Technology (NCNST), Beijing 100083, PR China. Electronic address: fenghongqing@binn.cas.cn.
Hongqing
H
Feng
Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China. Electronic address: paul.chu@cityu.edu.hk.
Paul K
PK
Chu
D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000737:chemistry; D018407:Bacterial Physiological Phenomena / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D004343:Drug Implants / Q000008:administration & dosage / Q000737:chemistry; D004553:Electric Conductivity; D004579:Electron Transport; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000008:administration & dosage* / Q000737:chemistry; D017382:Reactive Oxygen Species / Q000378:metabolism*; D012834:Silver / Q000008:administration & dosage* / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
D000900:Anti-Bacterial Agents; D004343:Drug Implants; D017382:Reactive Oxygen Species; D012834:Silver; D014025:Titanium
Antibacterial mechanism; Electron transfer; Reactive oxygen species; Silver nanoparticles; Titanium