Hybrid systems based on avobenzone–wrinkled mesoporous silica as ingredients of sunscreen formulations

Abstract

Excessive exposure to solar radiation causes skin reddening, and sunburn, may accelerate photoaging processes, and lead to neoplastic changes. Therefore, it is recommended to apply cosmetic formulations containing UV protection filters. In recent years, doubts have arisen regarding the safety of certain chemical sunscreen agents that can penetrate the deeper layers of the skin, undergo photodegradation, generate allergies, and affect the endocrine system. The aim of this study was to develop a strategy to limit the permeation of avobenzone from emulsions. Wrinkled mesoporous silicas modified with zinc oxide and/or aminosilane were synthesized, characterized, and next applied as the carriers for the selected UV filter – avobenzone. The introduction of organic groups and ZnO did not disturb the wrinkled morphology of materials, but it changed the textural parameters due to the blocking of micropores. The modification of the wrinkled mesoporous silica had a positive effect on reducing avobenzone rate of desorption. The smallest amount of avobenzone was released from wrinkled mesoporous silica modified with zinc oxide. The release of avobenzone from nanocarriers followed the Korsmeyer-Peppas model, while the diffusion from emulsion was based on the Higuchi model. It was proved that the introduction of avobenzone to functionalized wrinkled mesoporous silica materials reduced the diffusion process of avobenzone from cosmetic emulsions. Nanoporous carriers may help solve the problems related to transepidermal penetration and the potential impact of UV filters on the endocrine system.