A Novel Hydrophilic Adhesive Matrix with Self-Enhancement for Drug Percutaneous Permeation Through Rat Skin

Purpose. In transdermal drug delivery system (TDDS), chemical enhancers and crystallization inhibitors added into the adhesive matrixes to improve drug permeation and formulation stability often result in some negative effect on adhesive properties and dressing performance. The aim of this paper is to develop a hydrophilic pressure sensitive adhesive (PSA) for TDDS without using additional chemical enhancers and crystallization inhibitors. Methods. A quaternary blend (PDGW) composed of polyvinyl pyrrolidone, D,L-lactic acid oligomers, glycerol and water was prepared. The adhesive strength, drug loading capacity, drug state and stability of PDGW were characterized by using ibuprofen (IBU) and salicylic acid (SA) as model drugs. Moreover, In vitro and in vivo drug permeation through rat skin from PDGW patch in comparison to acrylate adhesive (ACA) and nature rubber adhesive (NRA) was investigated. Results. PDGW performs excellent drug loading and crystallization inhibition capacity. Furthermore, the accumulative amount for 24 h in vitro from PDGW patch is far higher than that from ACA and NRA patch. And the plasma concentration of drugs in vivo from PDGW patch is bigger than that from ACA patch. Conclusions. PDGW possesses excellent PSA properties and self-enhancement for drug percutaneous permeation, which can be used to develop new formulation of TDDS. KEY WORDS: D,L-lactic acid oligomers; hydrophilic adhesive matrix; polyvinyl pyrrolidone; transdermal drug delivery system