Study of Anti-UVA/UVB Sunscreen Gels Based on Solid Lipid Nanoparticles

OBJECTIVE To prepare the sunscreen hydrogel in order to prevent harm of UVA and UVB, and evaluate its morphology, size and ultraviolet absorption. METHODS Octyl methoxycinnamate (OMC)-loaded solid lipid nanoparticles (SLN) (141 nm) for UVB prevention and 4'-tert-butyl-4-methoxy-dibenzoylmethane(TBMD)-loaded SLN (104 nm) for UVA prevention were prepared with the emulsion-dispersion method. Nanoscale titanium dioxide was as the physical sunscreen agent and hyaluronic acid was as the hydrogel matrix and the moisture agent. Size, ultraviolet absorption and morphology were as the evaluation indices. Sunscreen hydrogel to prevent harm of UVA and UVB was prepared finally after optimization. RESULTS The best drug loading ratio of OMC-SLN and TBMD-SLN was 4% and 3%, respectively. The size were 141, 104 nm, respectively. Their ultraviolet absorption range was 250-350, 280-400 nm, respectively. The appearance of the optimized sunscreen hydrogel was white, fine, and uniform emulsion. The higher ultraviolet absorption appeared in the range of 280-720 nm. It demonstrated that the effect of prevention for UVA and UVB was good. The excellent prevention effect of UVA/UVB was also validated on guinea pig. CONCLUSION Sunscreen hydrogel with OMC-and TBMD-loaded SLN will become a promising formulation for prevention of UVA and UVB.