title: "On-off" thermocontrol of solute transport. II. Solute release from thermosensitive hydrogels.
abstract: Poly(N-isopropylacrylamide) (NIPAAm)/polytetramethylene ether glycol (PTMEG) interpenetrating polymer networks (IPNs) were synthesized and their feasibility as thermosensitive hydrogels for drug release was investigated. The release of indomethacin incorporated into these matrices showed pulsatile patterns in response to temperature changes and was sensitive to a few degrees of temperature fluctuation. The temperature inducing on-off release deviated from the gel collapse temperature of unloaded gel, possibly because of solute effects on network properties. The lag time and release profile of indomethacin in the low-temperature region (on process) of each temperature cycle were affected by the gel composition and applied temperature. The results of this study demonstrate that solute release can be regulated by rapid deswelling of the surface of the gels in response to temperature.
authors.affiliation: Department of Pharmaceutics, University of Utah, Salt Lake City 84112.
authors.forename: Y H
authors.initials: YH
authors.lastname: Bae
authors.forename: T
authors.initials: T
authors.lastname: Okano
authors.forename: S W
authors.initials: SW
authors.lastname: Kim
mesh_terms: D004337:Drug Carriers; D005782:Gels; D007213:Indomethacin / Q000008:administration & dosage / Q000493:pharmacokinetics*; D014677:Pharmaceutical Vehicles; D011108:Polymers; D013696:Temperature; D014867:Water
chemical_list: D004337:Drug Carriers; D005782:Gels; D014677:Pharmaceutical Vehicles; D011108:Polymers; D014867:Water; D007213:Indomethacin