Antibacterial property improvement of nano-MgO prepared by lithium doping under nitrogen calcination

MgO nanomaterial (nano-MgO) is a promising candidate in the antibacterial field owing to its large reserves, low cost, high stability, and safety to both the environment and human beings. However, the actual application of nano-MgO is restricted by its relatively low antibacterial activity. In the present work, we report the fabrication of modified nano-MgO via lithium (Li) ion doping and an oxygen-deficient calcination process. The antibacterial ratio of Li/MgON at 100 mu g/mL was about 99.6% against 10(8) CFU/mL Escherichia coli (E. coli, ATCC 25922), suggesting that the antibacterial activity was successfully enhanced compared with that of pure MgO and Li/MgO calcined in air. This superior activity mainly originated from the increased number of oxygen vacancies based on the synergetic effects of Li doping and N-2 calcination, resulting in more center dot O-2(-) generation. The disinfection of drinking water tests showed that Li/MgON quickly killed E. coli in 1 h and retained high activity over 30 days. These results indicated that the formation of modified nano-MgO by Li doping and N-2 calcination is a novel and effective approach to obtain a promising MgO-based antibacterial agent with highly effective antibacterial property and durability.

Automated summary

In this study, modified nano-MgO with enhanced antibacterial activity was successfully fabricated through lithium ion doping and calcination in a nitrogen atmosphere. The modified nano-MgO showed superior antibacterial properties and durability, making it a promising MgO-based antibacterial agent.