Skin Penetration Ability of 12 Hyaluronic Acids with Different Molecular Weights After Topical Application

Objective: Hyaluronic acid (HA) is a fundamental component of the extracellular matrix, regulating numerous biological processes. In humans, almost half of the total HA concentrates in the skin, but its availability decreases with age. Therefore, topical exogenous supplies of HA can reduce the aging process of the skin and can represent a valid alternative to the costly and invasive treatments based on injectable HA-based fillers. However, for cosmetically effective topical preparations, it is crucial to determine the properties favouring percutaneous HA penetration, such as HA molecular weight (MW). Therefore, the ability of 12 HA molecules with different MWs to penetrate the skin using an in vitro model was examined. Materials and Methods: The Franz diffusion cell experimental system was used to estimate the penetration of the HA molecules across three epidermal tissues. The relationship between MW and penetration was inspected by applying a Pearson’s correlation test.