Understanding the structure of sunscreen formulations: where does the active sit?

The negative effects of exposure to ultraviolet rays, 290-400 nm, are well known. Long exposures to these rays often cause skin damage (e.g. skin burns, melanoma). Topical sunscreen formulations are then of particular interest given their protection against UV damage. These formulations are often comprised of mixtures of active (chemical and physical UV filters) and inactive (polymers, surfactants, silicones, vitamins) ingredients. The interactions between these different components often decide where the active ingredient sits in a formulation. Here, we wish to study the interactions between a range of UV filters with one of the inactive ingredients used in several of these formulations; Poloxamer or Pluronic.