TOPICAL COMPOSITION WITH ENHANCED PHOTOPROTECTION PROPERTIES

摘要

It has been determined that topical compositions comprising nanocrystalline cellulose and at least one excipient exhibit enhanced photoprotection properties. They are therefore useful as sunscreens to protect against harmful ultraviolet (UV) radiation, hi preferred embodiments, the composition is a cream comprising at least about 2 % by weight of the nanocrystalline cellulose. The length, diameter, and aspect ratio of the crystals making up the nanocrystalline cellulose, as well as the crystallinity index (CRI) also preferably fall within select bounds. In an exemplary7 embodiment, the nanocrystalline cellulose is prepared by a process involving selective oxidation of the C6 primary7 hydroxyl groups, thereby introducing carboxylrc acrd groups on the surface of the nanocrystalline cellulose and yielding the aforementioned desired crystalline properties.