Adhesive Composite Hydrogel Patch Based on a Polyaspartamide Derivative to Treat Atopic Dermatitis

Abstract

Transdermal patches offer significant advantages as a drug delivery system due to their ability to bypass first‐pass metabolism, sustain drug release, and provide predetermined dose and application area. However, to be effective, transdermal patches must have optimal adhesion and drug‐loading capacity. In this study, an adhesive composite hydrogel patch consisting of poly(N‐2,3‐dihydroxypropyl aspartamide) (PDHPA), a polyaspartamide derivative, and mesoporous silica nanoparticles (MSNs) are developed. To prepare the hydrogel, boric acid (BA) is utilized as a crosslinker to form reversible bonds between multiple hydroxyl groups in the polymer and BA. The PDHPA‐BA hydrogel exhibits dynamic reversibility, self‐healing properties, and a pH‐dependent sol–gel transition. The addition of MSNs with abundant hydroxyl groups improves the mechanical performance, adhesion properties, and self‐healing rate of the PDHPA‐BA hydrogel. In addition, MSNs enable the loading of hydrophobic drugs, such as dexamethasone (Dex), onto the hydrogel. Using the Dex‐loaded adhesive composite hydrogel as a transdermal patch, the severity of atopic dermatitis in a mouse model indicated by suppression of dermatitis score, epidermal thickness, number of mast cells, and serum interleukin‐4 levels is successfully reduced. These results suggest that the composite hydrogel patch is a highly promising transdermal drug delivery system for effectively treating inflammatory skin diseases.