Fig. 6.

(a) The mechanism of bacterial annihilation proposed in the current literature indicates that the suspended TiO₂ powder covers the bacteria, while the photogenerated ROS drive the lysis of the cell wall. The cellular content is expelled killing the microbe. The AgNPs also form complexes with the DNA and RNA of the microorganisms causing the loss of cellular replication capacity. (b) In fact, the real mechanism is more complex and diverse for each type of microbes. The information necessary to understand the interactions of TiO₂ and the cell wall of microorganisms are shown considering their characteristics.