title: Glucose-responsive insulin delivery microhydrogels from methacrylated dextran/concanavalin A: preparation and in vitro release study.
abstract: Glucose-responsive systems are very important for self-regulated insulin delivery. The aim of the present study was to evaluate the potential of insulin loaded microhydrogels fabricated from methacrylate derivatives of dextran (Dex-G) and concanavalin A (Con A-E) as a insulin delivery system releasing insulin in response to different glucose levels. Insulin-loaded microhydrogels were prepared through a reversed-phase emulsion crosslinking method. The morphology and size of obtained microhydrogels were characterized by SEM, fluorescence microscope and dynamic light scattering, which showed that these microhydrogels were formed with sphere-like shape and diameters less than 5 μm. In vitro release of insulin from these microhydrogels and release kinetics were studied. The results indicated that insulin release was reversible in response to different glucose concentrations and the released insulin was shown to remain active since the tertiary structure was not destroyed. The degree of substitution (DS) of dextran methacrylate derivatives had effects on the release rate and surface burst release of the microhydrogels and high DS of Dex-G (DS 32) restricted the glucose sensitivity of the microhydrogels. The MTT assay from L929 cell line indicated that these microhydrogels possessed noncytotoxicity. The results suggested that these microhydrogels might be suitable for self-regulated insulin delivery and find potential applications in biomedical fields.
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China.
authors.forename: Ruixue
authors.initials: R
authors.lastname: Yin
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China.
authors.forename: Zi
authors.initials: Z
authors.lastname: Tong
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China.
authors.forename: Dongzhi
authors.initials: D
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China; College of Chemistry and Molecular Science, Wuhan University, Wuhan 430072, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Nie
mesh_terms: D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003208:Concanavalin A / Q000008:administration & dosage / Q000737:chemistry; D003911:Dextrans / Q000008:administration & dosage / Q000737:chemistry; D004339:Drug Compounding; D016503:Drug Delivery Systems; D065546:Drug Liberation; D005947:Glucose / Q000737:chemistry; D020100:Hydrogels; D007328:Insulin / Q000008:administration & dosage / Q000737:chemistry; D008689:Methacrylates / Q000008:administration & dosage / Q000737:chemistry; D051379:Mice
chemical_list: D003911:Dextrans; D020100:Hydrogels; D007328:Insulin; D008689:Methacrylates; C514458:methacrylated dextran; D003208:Concanavalin A; D005947:Glucose