Microneedles containing collagen, hyaluronic acid, and cinnamoyl-functionalized poly(hydroxyethyl acrylate-co-butyl methacrylate) with light- and temperature-dependent transdermal delivery properties
摘要
This work reports a ultraviolet (UV)- and temperature-responsive dissolving microneedle matrices based on cinnamoyl-functionalized poly(hydroxyethyl acrylate-co-butyl methacrylate) (Cin-poly(HEA-co-BMA)) for controllable transdermal delivery. The lower critical solution temperature (LCST) of the copolymer decreased with increasing hydrophobic moieties, while UV irradiation increased the LCST via cinnamoyl photoreaction, enabling light-regulated thermal responsiveness. Pyramidal microneedle matrices exhibited an elastic–fracture–elastic deformation behavior under compression, with a Young’s modulus of 0.187–0.221 MPa, and UV treatment further enhanced their mechanical strength. Nearly 100% skin penetration efficiency was achieved, particularly for UV-treated needles. Dye permeation at 37 °C was significantly higher than that at 25 °C, whereas UV irradiation effectively suppressed this thermally promoted permeation by elevating the LCST. This dual-responsive microneedle matrix system provides a programmable strategy for mechanically robust and externally regulated transdermal delivery.