title: Composite block polymer-microfabricated silicon nanoporous membrane.
abstract: Block polymers offer an attractive route to densely packed, monodisperse nanoscale pores. However, their fragility as thin films complicates their use as membranes. By integrating a block polymer film with a thin (100 microm) silicon substrate, we have developed a composite membrane providing both nanoscale size exclusion and fast transport of small molecules. Here we describe the fabrication of this membrane, evaluate its mechanical integrity, and demonstrate its transport properties for model solutes of large and small molecular weight. The ability to block large molecules without hindering smaller ones, coupled with the potential for surface modification of the polymer and the microelectromechanical system style of support, makes this composite membrane an attractive candidate for interfacing implantable sensing and drug-delivery devices with biological hosts.
authors.affiliation: Department of Pharmaceutics, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors.forename: Eric E
authors.initials: EE
authors.lastname: Nuxoll
authors.forename: Marc A
authors.initials: MA
authors.lastname: Hillmyer
authors.forename: Ruifang
authors.initials: R
authors.lastname: Wang
authors.forename: C
authors.initials: C
authors.lastname: Leighton
authors.forename: Ronald A
authors.initials: RA
authors.lastname: Siegel
mesh_terms: D003460:Crystallization / Q000379:methods; D008422:Materials Testing; D008567:Membranes, Artificial; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D016062:Porosity; D012825:Silicon / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D008567:Membranes, Artificial; D011108:Polymers; D012825:Silicon