Preparation and characterization of titanium oxide nanocapsules containing retinoic acid for sustained release

Abstract

Abstract Retinoic acid (RA) has been widely used in cosmetics and medicine. However, high concentrations of RA could cause negative effects, and carcinogenic substances can be generated by light degradation. Herein, a convenient and environmental method was developed to realize the sustained release of RA by TiO2 nanocapsules. The surface morphologies, crystalline properties, and chemical structures were characterized by SEM, XRD, FT-IR, NMR. Moreover, the effects of solubilizer, core material content, shell-forming agent, biological properties, and other factors on the nanocapsules were investigated. The results indicated that low crystallinity of anatase TiO2 shell contributed to sustained release of inner RA. The sustained-release properties were studied through the elution process. It confirmed that the RA was encapsulated in the TiO2 shell with loose structures. Light irradiation experiments proved that inner RA was well protected and released continuously. The RA-TiO2 nanocapsules showed good dispersion, sustained-release properties, long-acting antibacterial property, and photostability.