A Smart Patch for Transdermal Drug Delivery

Transdermal drug delivery of ibuprofen, a well known NSAID has sparked considerable research interest in the recent years. The hydrophobic nature of the drug as well as its water insolubility is a significant deterrent for its uptake through the skin and its bioavailability at the targeted site of pain/inflammation. This work addresses both concerns through a novel microemulsion formulation synergizing the concepts of eutectic points and microemulsification. A eutectic composition of ibuprofen (IBP) with a proprietary polymer formulation (pro-drug) was micro-emulsified with a biocompatible emollient (Shea butter) or a suitable common solvent (ethyl acetate) to produce two types of O/W emulsions. The eutectic composition allows the IBP/pro-drug formulation to melt at skin temperature and the microemulsion system ensures that the IBP/pro-drug formulation is encapsulated in micron sized droplets to facilitate transdermal absorption on account of increased surface area. In applying the formulation onto a textile, the dispersed phase (water) is evaporated leaving behind micron sized droplets of the oil phase on the textile.