Safer-by-design hybrid nanostructures: an alternative to conventional titanium dioxide UV filters in skin care products

For sustainable development of nanotechnology, nanomaterials should follow a safer-by-design approach so that the associated exposure and hazard risks throughout their entire life cycle can be minimized without compromising their functioning efficiency. In this context, we present organic-inorganic hybrid nanostructures composed of titanium dioxide (TiO2) nanoparticles grafted onto cellulose nanocrystals (CNC) using a sol-gel process. After grafting optimization, we show that the overall efficiency of these hybrid nanostructures to filter UV rays can be higher than their conventional counterparts. At the same time, these hybrid nanostructures are proven to stabilize Pickering emulsions, replacing surfactant in formulation. Hence, they may serve as an ideal alternative to the conventionally used inorganic filters and stabilizers in various applications such as skin care products