title: Synthesis of glucose-responsive bioconjugated gel particles using surfactant-free emulsion polymerization.
abstract: Bioconjugated gel particles that have complexes composed of lectin concanavalin A (ConA) and 2-glucosyloxyethyl methacrylate (GEMA) were synthesized by the surfactant-free emulsion copolymerization of N,N-diethylaminoethyl methacrylate (DEAEMA), poly(ethylene glycol) dimethacrylate (PEGDMA), GEMA, and modified-ConA with polymerizable groups. The resultant gel particles having GEMA-ConA complexes (GEMA-ConA gel particles) were colloidally stable in a phosphate buffer solution and had a diameter of approximately 750nm. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) measurements implied that GEMA-ConA gel particles have core-shell structures consisting of a hydrophobic core of DEAEMA and a hydrophilic shell of GEMA and PEGDMA containing ConA. GEMA-ConA gel particles underwent a change in size in response to glucose in a phosphate buffer solution. The swelling ratio of GEMA-ConA gel particles gradually increased with an increase in the glucose concentration. On the other hand, the swelling ratio of GEMA-ConA gel particles remained unchanged in a phosphate buffer solution containing galactose. The glucose-responsive swelling of GEMA-ConA gel particles was induced by the dissociation of GEMA-ConA complexes acting as reversible cross-links, because free glucose behaved as an inhibitor of GEMA-ConA complexes. These results indicate that GEMA-ConA gel particles can recognize glucose selectively and undergo changes in size in response to the glucose concentration. The smart functions of glucose-responsive gel particles can provide tools for constructing self-regulated drug delivery systems and sensor systems useful for treating diabetes.
authors.affiliation: Organization for Research and Development of Innovative Science and Technology, Kansai University, Suita, Osaka 564-8680, Japan.
authors.forename: Akifumi
authors.initials: A
authors.lastname: Kawamura
authors.forename: Yuta
authors.initials: Y
authors.lastname: Hata
authors.forename: Takashi
authors.initials: T
authors.lastname: Miyata
authors.forename: Tadashi
authors.initials: T
authors.lastname: Uragami
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D002021:Buffers; D003208:Concanavalin A / Q000737:chemistry*; D004337:Drug Carriers / Q000138:chemical synthesis*; D004655:Emulsions; D005690:Galactose / Q000737:chemistry; D005782:Gels; D005947:Glucose / Q000032:analysis* / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D008689:Methacrylates / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry; D056951:Photoelectron Spectroscopy; D011092:Polyethylene Glycols / Q000737:chemistry; D058105:Polymerization; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D002021:Buffers; D004337:Drug Carriers; D004655:Emulsions; D005782:Gels; D008689:Methacrylates; D010710:Phosphates; C421283:poly(ethylene glycol)-dimethacrylate; D003208:Concanavalin A; D011092:Polyethylene Glycols; D005947:Glucose; C519537:diethylaminoethyl methacrylate; D005690:Galactose