Antibacterial Properties of Multi-walled Carbon Nanotubes Decorated with Silver Nanoparticles

Background: Antibacterial materials have attracted much attention due to its important role in human health and safety. Therefore the development and exploitation of novel antibacterial materials and agents with highly effective antibacterial activity are very necessary. Methods: A simple method to prepare antibacterial multi-walled carbon nanotubes (MWCNTs) was described. MWCNTs were coated with a reactive polydopamine (PDA) layer by dispersing them in dopamine (DA) solution, followed with chemical deposition of silver nanoparticles (Ag NPs) on the PDA layer. Antibacterial activity of MWCNTs@PDA@Ag NPs towards E. coli and S. aureus was estimated by standard plate count method. Results: Spherical silver nanoparticles with size of 5-6 nm were uniformly decorated on the sidewalls of MWCNTs. The MWCNTs@PDA@Ag NPs composite shows a good antibacterial property towards E. coli and S. aureus, with an antibacterial rate of 93.8% at the concentration of 6.25 mu g/mL and an antibacterial rate of 93.1% at the concentration of 2 mu g/mL, respectively. Conclusion: The MWCNTs@PDA@Ag NPs composite exhibits excellent antibacterial activity towards E. coli and S. aureus, and it is an ideal material for sterilization.