Antibacterial, antifungal, antiviral, and photocatalytic activities of TiO2nanoparticles, nanocomposites, and bio-nanocomposites: Recent advances and challenges

The applications of nanomaterials specifically metal and metal nanoparticles in various medical and industrial fields have been due to their unique properties compared to bulk materials. A combination of pharmacology and nanotechnology has helped the production of novel antimicrobial agents to control resistant microorganisms of bacteria and fungi. The properties of metal nanoparticles and metal oxides such as titanium dioxide (TiO 2 ), zinc oxide (ZnO), silver (Ag), and copper (Cu) are well known as efficient antimicrobial agents. In particular, TiO 2 nanoparticles have been considered as an attractive antimicrobial compound due to their photocatalytic intrinsic and their stable, non-toxic, inexpensive, and safe physicochemical properties. Therefore, in this review, recent advances and challenges of antibacterial, antifungal, antiviral, and photocatalytic activities of TiO 2 nanoparticles, nanocomposites, and bio-nanocomposites are presented to help future studies.