Transdermal Drug Delivery Adhesives with Foam Morphology

Abstract

Polyacrylate-based adhesives are common in commercial bandages for blister prevention and wound healing. In this research, pressure sensitive polyacrylate adhesive foams have been investigated that could potentially be used in transdermal drug delivery. A variety of foaming methods were investigated, such as high speed mixing, adding blowing agents, freeze drying, heating, and bulk polymerization of a reactive exothermic monomer. The products were characterized with FT-IR, tack, and peel resistance testing. A common drug was incorporated into the foams and its stability and release probability assessed. It was found that the drug impacted the viscosity and foam formation ability of the adhesive. Color changes were observed that suggested (partial) decomposition of the drug. Since the polymerization mechanism was free-radical addition, radical terminators (in particular chain transfer agents) were utilized in an effort to preserve the drug. The final drug loaded product was tested in a release trial to make a preliminary determination on the overall adhesive system’s suitability. Finally, peel tests were conducted of the drug loaded samples and compared to those of commercial acrylate adhesives.