Controlled release of model drugs through a molecular recognition ion gating membrane in response to a specific ion signal.
A controlled-release device that responds to a specific molecular signal is an ideal goal in drug delivery and tissue engineering. A molecular recognition ion gating membrane, in which a copolymer of N-isopropylacrylamide and benzo[18]-crown-6-acrylamide was grafted onto the surface of the porous polyethylene film, was used to control the permeability of vitamin B12 and lysozyme in response to a specific ion signal. The observed response depended on the amount of grafted copolymer. When the grafting ratio was below 15%, the membrane pores opened by Ca2+ and closed by Ba2+. The permeability of model drugs became higher by opening of the pores. On the other hand, when the grafting ratio was above 15%, the properties of the membrane changed. The permeability of model drugs became lower by Ca2+ due to dehydration of the grafted copolymer. The opposite responses were observed at different grafting ratios.
Department of Chemical System Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku Tokyo, 113-8656 Japan.
Taichi
T
Ito
Takeo
T
Yamaguchi
D000180:Acrylic Resins / Q000737:chemistry; D001464:Barium / Q000737:chemistry; D002118:Calcium / Q000737:chemistry; D002626:Chemistry, Pharmaceutical / Q000379:methods; D002627:Chemistry, Physical / Q000379:methods*; D016503:Drug Delivery Systems; D008567:Membranes, Artificial; D008956:Models, Chemical; D020959:Polyethylene / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D016062:Porosity; D012995:Solubility; D013678:Technology, Pharmaceutical / Q000379:methods; D023822:Tissue Engineering / Q000379:methods
D000180:Acrylic Resins; D008567:Membranes, Artificial; D011108:Polymers; D001464:Barium; C052970:poly-N-isopropylacrylamide; D020959:Polyethylene; D002118:Calcium