title: Fluorination of electrospun hydrogel fibers for a controlled release drug delivery system.
abstract: Electrospinning and fluorination were carried out in order to obtain a controlled release drug delivery system to solve the problem of both an initial burst of the drug and a limited release time. Poly(vinyl alcohol) was electrospun with Procion Blue as a model drug and heat treated in order to obtain cross-linked hydrogel fibers. Two different kinds of electrospun fibers of thin and thick diameters were obtained by controlling the electrospinning conditions. Thin fibers offer more available sites than thick fibers for surface modification during fluorination. Fluorination was conducted to control the release period by introducing hydrophobic functional groups on the surface of fibers. With an increase in the reaction pressure of the fluorine gas hydrophobic C-F and C-F(2) bonds were more effectively introduced. Over-fluorination of the fibers at higher reaction pressures of fluorine gas led to the introduction of C-F(2) bonds, which made the surface of the fibers hydrophobic and resulted in a decrease in their swelling potential. When C-F bonds were generated the initial drug burst decreased dramatically and total release time increased significantly, by a factor of approximately 6.7 times.
authors.affiliation: Department of Fine Chemical Engineering and Applied Chemistry, Chungnam National University, Daejeon 305-764, Republic of Korea.
authors.forename: Ji Sun
authors.initials: JS
authors.lastname: Im
authors.forename: Jumi
authors.initials: J
authors.lastname: Yun
authors.forename: Youn-Mook
authors.initials: YM
authors.lastname: Lim
authors.forename: Hyung-Il
authors.initials: HI
authors.lastname: Kim
authors.forename: Young-Seak
authors.initials: YS
authors.lastname: Lee
mesh_terms: D000818:Animals; D002021:Buffers; D016503:Drug Delivery Systems; D004563:Electrochemistry / Q000379:methods*; D005347:Fibroblasts / Q000166:cytology; D005461:Fluorine / Q000737:chemistry*; D005740:Gases; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry*; D020100:Hydrogels / Q000737:chemistry; D051379:Mice; D008855:Microscopy, Electron, Scanning / Q000379:methods; D011108:Polymers / Q000737:chemistry; D011142:Polyvinyl Alcohol / Q000737:chemistry; D013055:Spectrophotometry, Infrared / Q000379:methods; D014227:Triazines / Q000737:chemistry
chemical_list: D002021:Buffers; D005740:Gases; D020100:Hydrogels; D011108:Polymers; D014227:Triazines; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D005461:Fluorine; C012842:Cibacron Blue F 3GA; D011142:Polyvinyl Alcohol