| abstract |
Provided herein are formulation bases comprising a nanogel comprising a first fraction of hyaluronic acid, or a pharmaceutically acceptable salt thereof, and a second fraction of hyaluronic acid, or a pharmaceutically acceptable salt thereof; and lecithin liposomes within the nanogel, the lecithin liposomes having a d75 of from about 25 nm to about 250 nm, wherein the hyaluronic acid of the first fraction, or a pharmaceutically acceptable salt thereof, has a molecular weight of greater than about 500 kilodaltons, and the hyaluronic acid of the second fraction, or a pharmaceutically acceptable salt thereof, has a molecular weight of less than about 250 kilodaltons. The formulation bases described herein provide for absorption of active substances contained therein into the body, e.g., transdermally, and, therefore, can be used as delivery systems to administer one or more active substances to a subject. |