Physicochemical study on microencapsulation of hydroxypropyl-beta-cyclodextrin in dermal preparations.

Objective: To investigate the effect of hydroxypropyl-beta-cyclodextrin (HP-beta-CD) concentration on the physicochemical properties of the sunscreen agents, namely oxybenzone (Oxy), octocrylene (Oct), and ethylhexyl-methoxy-cinnamate (Cin), in aqueous solution and cream formulations.

Methods: The inclusion complexes of sunscreen agents with hydroxypropyl-beta-cyclodextrin (HP-beta-CD) in aqueous solution and solid phase were studied by UV-vis spectrophotmetery, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and 13C-NMR techniques. The photodegradation reaction of the sunscreen agents' molecules in lotion was explored using UV-vis spectrophotometry and high-performance liquid chromatography (HPLC).