To
effectively shield the full band of ultraviolet (UV)
radiation
and provide desirable protection, the combination of inorganic and
organic filters was often used to protect human skin from the serious
harm of UV exposure. However, the incompatibility of different filters
and their mutual negative effect limit the production of multifilter
sunscreen. In addition, the hazard of reactive oxygen species (ROS)
produced by inorganic filters after UV exposure and the skin permeability
of organic filters remain unresolved problems. In this study, titanium
dioxide (TiO2) and diethylamino hydroxybenzoyl hexyl benzoate
(DHHB), two kinds of common filters with complementary UV shielding
range, were first encapsulated into large mesoporous silica nanoparticles
(MSN, ∼300 nm) to obtain MSN-TiO2 and MSN-DHHB.
Also, a SiO2 coating was then made to seal and stabilize
the MSN-TiO2 and MSN-DHHB. The structure, UV screen function,
and safety of the SiO2-coated filters, MSN-TiO2@SiO2 and MSN-DHHB@SiO2, were evaluated. The
good mechanical stability exhibited by the solid SiO2 layer
prevented the release and skin penetration of the sealed DHHB and
the photocatalysis of TiO2. Furthermore, the combination
of MSN-TiO2@SiO2 and MSN-DHHB@SiO2 in sunscreen cream showed excellent UV shielding performance on
covering the whole UV radiation range without mutual interference.
Therefore, coating SiO2 over MSN is a feasible strategy
for entrapping various filters to improve their photostability, preventing
skin penetration and ROS generation, and enhancing their compatibility
with different sunscreen formulations.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.