Development of gellan gum containing formulations for transdermal drug delivery: Component evaluation and controlled drug release using temperature responsive nanogels

[Display omitted] Enhancing skin permeation is important for development of new transdermal drug delivery formulations. This is particularly relevant for non-steroidal anti-inflammatory drugs (NSAIDs). To address this, semisolid gel and solid hydrogel film formulations containing gellan gum as a gelling agent were developed and the effects of penetration enhancers (dimethyl sulfoxide, isopropyl alcohol and propylene glycol) on transport of the NSAID diclofenac sodium was quantified. A transwell diffusion system was used to accelerate formulation development. After 4h, diclofenac flux from a superior formulation of the semisolid gel or the solid hydrogel film was 130±11μg/cm2h and 108±7μg/cm2h, respectively, and significantly greater than that measured for a currently available diclofenac sodium topical gel (30±4μg/cm2h, p