Protecting the hair, skin, or products of itself are utilized by sunscreen filters which were
frequently blocked hazardous UV-Vis radiation. Considering its photoprotective impact on the skin
facing the radiation of ultraviolet and visible, TiO2 is a common and cost-efficient photocatalytic
structure utilized in sunscreens. In this research, the continual process was done to optimize the green
synthesis of TiO2 nanoparticles and nanocomposites through a new, easy, cost-efficient, and quick
approach to making nanostructures utilizing a sonochemistry method. SiO2, Al2O3, ZnO, and MnO were
utilized to compose green synthesized TiO2 nanoparticlesfor this purpose. The samples were recognized
by XRD, FT-IR, DLS, and SEM. Also, the cytotoxicity and antibacterial activity were assessed. DFT
computation was performed to identify the connected energy and band gap energy of nanocomposites
by B3LYP/Lan2DZ quantum approach. TiO2/Al2O3 showed a lower size and the lowest agglomeration
than synthesized TiO2 and other nanocomposites. Furthermore, all samples indicated strongantibacterial activity against investigated bacteria due to cell death caused by membrane permeability
increase and bacterial wall integrity disruption. Nanostructures have cytotoxicity with a low level
on A172 cells. The only exception is TiO2/ZnO which indicated a potent index of cytotoxicity on the cancerous
cell lines as demonstrated by a low IC50 value of 50 ppm. The relative energy and band gap of nanocomposites
indicated that TiO2/Al2O3 has the best stability in chemical and biochemical mediums among other
nanocomposites. These green synthesized TiO2/Al2O3 nanostructures may have promising applications
in nanoformulation to combat bacterial infections in the future.
