title: Graft copolymer-templated mesoporous TiO(2) films micropatterned with poly(ethylene glycol) hydrogel: novel platform for highly sensitive protein microarrays.
abstract: In this study, we describe the use of organized mesoporous titanium oxide (TiO(2)) films as three-dimensional templates for protein microarrays with enhanced protein loading capacity and detection sensitivity. Multilayered mesoporous TiO(2) films with high porosity and good connectivity were synthesized using a graft copolymer consisting of a poly(vinyl chloride) (PVC) backbone and poly(oxyethylene methacrylate) (POEM) side chains as a structure-directing template. The average pore size and thickness of the TiO(2) films were 50-70 nm and 1.5 μm, respectively. Proteins were covalently immobilized onto mesoporous TiO(2) film via 3-aminopropyltriethoxysilane (APTES), and protein loading onto TiO(2) films was about four times greater than on planar glass substrates, which consequently improved the protein activity. Micropatterned mesoporous TiO(2) substrates were prepared by fabricating poly(ethylene glycol) (PEG) hydrogel microstructures on TiO(2) films using photolithography. Because of non-adhesiveness of PEG hydrogel towards proteins, proteins were selectively immobilized onto surface-modified mesoporous TiO(2) region, creating protein microarray. Specific binding assay between streptavidin/biotin and between PSA/anti-PSA demonstrated that the mesoporous TiO(2)-based protein microarrays yielded higher fluorescence signals and were more sensitive with lower detection limits than microarrays based on planar glass slides.
authors.affiliation: Department of Chemical and Biomolecular Engineering, Yonsei University, 134 Sinchon-Dong, Seodaemoon-Gu, Seoul 120-749, Republic of Korea.
authors.forename: Kyung Jin
authors.initials: KJ
authors.lastname: Son
authors.forename: Sung Hoon
authors.initials: SH
authors.lastname: Ahn
authors.forename: Jong Hak
authors.initials: JH
authors.lastname: Kim
authors.forename: Won-Gun
authors.initials: WG
authors.lastname: Koh
mesh_terms: D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry*; D055767:Immobilized Proteins / Q000737:chemistry* / Q000378:metabolism; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D056951:Photoelectron Spectroscopy; D011092:Polyethylene Glycols / Q000737:chemistry*; D011143:Polyvinyl Chloride / Q000737:chemistry; D016062:Porosity; D040081:Protein Array Analysis / Q000295:instrumentation*; D014025:Titanium / Q000737:chemistry*
chemical_list: D055767:Immobilized Proteins; D008689:Methacrylates; C009495:titanium dioxide; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D011092:Polyethylene Glycols; D011143:Polyvinyl Chloride; D014025:Titanium