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J. Cosmet. Sci., 64, 9–17 ( January/February 2013) 9 Preparation and characterization of cosmeceutical liposomes loaded with avobenzone and arbutin JUN-JEN LIU, SAMI NAZZAL, TZU-SHAN CHANG, and TSUIMIN TSAI, School of Medical Laboratory Science and Biotechnology, Taipei Medical University, Taipei 110, Taiwan (J.-J.L.), Department of Basic Pharmaceutical Sciences, College of Pharmacy, University of Louisiana at Monroe, Monroe, LA 71201 (S.N.), and Graduate Institute of Biomedical Materials and Engineering, Taipei Medical University, Taipei 110, Taiwan (T.-S.C., T.T.). Accepted for publication May 9, 2012. Synopsis The objective of this study was to develop and characterize a liposome delivery system coencapsulating two cosmeceutical ingredients, avobenzone (AVO) and arbutin (AR). Two different liposome preparation meth- ods, that is, thin fi lm hydration and reverse-phase evaporation, were evaluated. To obtain the optimal formu- lation, various ratios of lipid to AVO or AR were tested. The effects of liposome formulation and preparation method on particle size, entrapment effi ciency (EE), and skin permeation rate were studied. The mean par- ticle size of the liposome formulations obtained by the thin fi lm hydration method was smaller than that obtained by the reverse-phase evaporation method. The EE of AR and AVO in liposomes prepared by the thin fi lm method, however, was lower than that prepared by the reverse-phase evaporation method. No differences in membrane permeation were observed between the two preparation methods. A large portion of AR perme- ated through the membrane into the receptor chamber. On the other hand, AVO remained in the donor chamber or accumulated in the membrane. The results of this study revealed that liposomes are a promising delivery system for coencapsulated AR and AVO. Liposomes may aid in retaining the sunscreen (AVO) at the surface of the skin for sun protection meanwhile facilitating the penetration of the whitening agent (AR) into the deeper layers of the skin for whitening effect. INTRODUCTION Ultraviolet radiation (UVR) emitted by sun can damage collagen fi bers and accelerate skin aging and is a major cause of skin cancer. To prevent skin damage by sunlight, physical coverage, such as clothing and sunglasses, is the most effective way to prevent sunburn and skin cancer caused by UVR. Applying sunscreens is also helpful in protecting the skin. An effi cient sunscreen product, however, should provide effective broad-spectrum protection across the UVR range (280–400 nm). An example of a highly effective sunscreen ingredi- ent with broad-spectrum protection is butyl methoxydibenzoylmethane or avobenzone Address all correspondence to Tsuimin Tsai at tmtsai00@tmu.edu.tw.