Anti - oxidant coated liposome as the delivery system for papain based natural cosmetics

Liposome is a topical delivery system that has evoked a considerable interest in the cosmetic industry. Liposome is biocompatible, biodegradable, exhibits low toxicity and has the ability to entrap both hydrophilic and lipophilic active materials [1]. Over the last decades, liposome has been intensively studied as nanocarriers for transdermal administration of drugs and skin care active ingredients [2]. Papain, a protease, is an exfoliating agent which has also been touted to be able to reduce the signs of aging. In this study, liposome was used to enhance the transdermal penetration of papain into the skin [2]. In addition, liposome also stabilizes papain and reduces skin damage due to direct exposure to papain. Liposome can be formed from pure L-a-phosphatidylcholine or from cheaper sources such as soybean lecithin. However, liposome from soybean lecithin can be oxidized easily due to its unsaturated fatty acid chains. To overcome this problem, in this work antioxidant was added to decrease liposome oxidation and thus increase stability. The liposome, which was at pH 6.5, was stored at 25°C and 4°C and the stability of the liposome was monitored up to sixty days. Coated liposome was found to be more stable than uncoated liposome regardless of storage temperature. After two months, the encapsulation efficiency of the coated liposome was approximately 80%, whilst the encapsulation efficiency of the uncoated liposome was approximately 74%. Percutaneous penetration study was conducted to assess the efficiency of the transdermal delivery of the liposome-papain through the skin. Results obtained from the analysis showed that liposome-papain effectively penetrated the skin. Various studies have suggested that liposome increases percutaneous penetration of compounds through interaction of vesicles with the stratum corneum [3] and that this penetration is responsible for the greater concentration of the active ingredient in the skin.