Preparation of Biocompatible Starch Nanoparticles Adsorbing Organic Sunscreen Agents and Their UV Protection Properties and Photostability

ABSTRACT Starch nanoparticles (SNPs) have garnered substantial attention due to their versatility, renewability, cost‐effectiveness, and biocompatibility. In this study, corn starch nanoparticles were prepared using ultrasound‐assisted chemical precipitation and subsequently adsorbed sunscreen agents, diethylamino hydroxybenzoyl hexyl benzoate and ethylhexyl methoxycinnamate to assess their sun protection effect. The particle size of the obtained SNPs was 153 nm, and the adsorption rate was 335.06%. The X‐ray diffraction analysis revealed a decrease in the crystallinity of starch from 37.4% to 28%, accompanied by a transformation from type A to type V. Notably, while maintaining the same quantity of organic sunscreen agent in the formulation, the sunscreen efficacy of sunscreen cream containing SNP‐adsorbed organic sunscreen agent (SNP‐A) was comparable to that of sunscreen cream containing TiO 2 . In contrast to sunscreen cream solely relying on organic sunscreen agents, when the organic sunscreen agent content in the SNPs‐A‐containing sunscreen cream was halved, the sun protection factor (SPF) and protection factor of UVA (PFA) values of the SNPs‐A‐containing sunscreen cream remained superior. Through the exploration of the adsorption properties of organic sunscreen agents onto corn starch nanoparticles and the subsequent sun protection effect, this study has developed an environmentally friendly and effective sunscreen material, namely nano‐starch, as a potential candidate. This material has achieved the objective of reducing the quantity of organic sunscreen agents in sunscreen creams or partially replacing inorganic sunscreen agents.