Lipid Nanoparticles as Novel Carrier for Broad-spectrum Sunscreen Formulations

摘要

The most widely used UVA absorber in broad-spectrum sunscreens is avobenzone. In the sunlight, however, it will be photolysised rapidly and its photoprotection against UVA will greatly decrease. A photoprotective formulation was developed with an increased sun protection factor(SPF), compared to a conventional formulations, but having the same concentration. In the present paper, the effectiveness of a sunscreen mixture, incorporated into the novel topical delivery systems, i.e. solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC), used as ultraviolet (UV) protector enhancers with a distinctly higher loading capacity has been developed and evaluated. After the production by hot high pressure homogenization, the NLC were analyzed in terms of particle size, physical state, particle shape, ultraviolet absorbance and stability. The determination of 3 organic UMilters was performed by HPLC with UV spectrophotometric detection. The loading capacities for molecular sunscreens reported before now are in the range of 10-15%. It was possible to load NLC with up to 40% with molecular sunscreen. The particle size for all NLC was around 300 nm after production. In the sunlight, the retention rate of avobenzone was up to 90% .