Mechanism of antibacterial activity of silver and praseodymium-loaded white carbon black

This paper investigated the antibacterial mechanism of the Ag-Pr-antibacterial white carbon black. The sol-gel method was used to prepare the carrier: white carbon black. Silver ion was selected to be the antibacterial ion, and praseodymium nitrate was selected to be the additive. The structure and antibacterial mechanism of this new inorganic antibacterial material were characterized by laser particle size analyzer, scanning electron microscope (SEM) techniques, energy dispersive spectrum (EDS) analysis, and antibacterial activity test (Escherichia coli as experimental bacterium). Results showed that the particle size of Ag-Pr-antibacterial White carbon black was less than 30 μm with a narrow size distribution. Ag+ is combined into the white carbon black by both the mode of ion exchange and the mode of adsorption process. The bacteriostasis rate of the Ag-Pr-antibacterial white carbon black was higher than that of the general Ag-antibacterial white carbon black. The antibacterial activity of Ag-Pr-antibacterial white carbon black was caused by the combination of contact and stripping antibacterial mechanism. The result also indicated that this new inorganic antibacterial material had good thermal and light stability.