title: Pulsatile peptide release from multi-layered hydrogel formulations consisting of poly(ethylene glycol)-grafted and ungrafted dextrans.
abstract: Multi-layered hydrogel formulations consisting of poly(ethylene glycol)-grafted dextran (PEG-g-Dex) and ungrafted Dex were investigated as a model of pulsatile drug release. In these formulations, it is considered that the grafted PEG domains act as a drug reservoir dispersed in the Dex matrix based on aqueous polymer two-phase systems. The formulations exhibited surface-controlled degradation by dextranase, and insulin release was observed in a pulsatile manner because of the multi-layered structure: PEG-g-Dex hydrogel layers containing insulin and insulin-free Dex hydrogel layers. Thus, it is suggested that the multi-layered hydrogel formulations using PEG-g-Dex and Dex are feasible for chronopharmacological drug delivery systems.
authors.affiliation: School of Materials Science, Japan Advanced Institute of Science and Technology, Tatsunokuchi, Ishikawa.
authors.forename: K
authors.initials: K
authors.lastname: Moriyama
authors.forename: T
authors.initials: T
authors.lastname: Ooya
authors.forename: N
authors.initials: N
authors.lastname: Yui
mesh_terms: D000818:Animals; D001673:Biodegradation, Environmental; D002214:Capsules / Q000737:chemistry*; D002417:Cattle; D003102:Colloids; D003911:Dextrans / Q000378:metabolism; D016503:Drug Delivery Systems; D004355:Drug Stability; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry* / Q000378:metabolism; D007328:Insulin / Q000378:metabolism*; D007700:Kinetics; D011092:Polyethylene Glycols / Q000378:metabolism; D011673:Pulsatile Flow
chemical_list: D002214:Capsules; D003102:Colloids; D003911:Dextrans; D007328:Insulin; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D011092:Polyethylene Glycols