title: Transdermal thiol-acrylate polyethylene glycol hydrogel synthesis using near infrared light.
abstract: Light-induced polymerization has been widely applied for hydrogel synthesis, which conventionally involves the use of ultraviolet or visible light to activate a photoinitiator for polymerization. However, with these light sources, transdermal gelation is not efficient and feasible due to their substantial interactions with biological systems, and thus a high power is required. In this study, we used biocompatible and tissue-penetrating near infrared (NIR) light to remotely trigger a thiol-acrylate reaction for efficient in vivo gelation with good controllability. Our gelation system includes gold nanorods as a photothermal agent, a thermal initiator, diacrylate polyethylene glycol (PEG), and thiolated PEG. Irradiation with a low-power NIR laser (0.3 W cm(-2)) could induce gelation via a mixed-mode reaction with a small increase in temperature (∼5 °C) under the optimized conditions. We also achieved successful transdermal gelation via the NIR-assisted photothermal thiol-acryl reactions. This new type of NIR-assisted thiol-acrylate polymerization provides new opportunities for in situ hydrogel formation for injectable hydrogels and delivery of drugs/cells for various biomedical applications.
authors.affiliation: School of Materials Science and Engineering, Gwangju Institute of Science and Engineering, Gwangju 500-712, Republic of Korea. jaeyounglee@gist.ac.kr.
authors.forename: Solchan
authors.initials: S
authors.lastname: Chung
authors.forename: Hwangjae
authors.initials: H
authors.lastname: Lee
authors.forename: Hyung-Seok
authors.initials: HS
authors.lastname: Kim
authors.forename: Min-Gon
authors.initials: MG
authors.lastname: Kim
authors.forename: Luke P
authors.initials: LP
authors.lastname: Lee
authors.forename: Jae Young
authors.initials: JY
authors.lastname: Lee