title: Protein attachment to nanoporous anodic alumina for biotechnological applications: influence of pore size, protein size and functionalization path.
abstract: Nanoporous anodic alumina (NAA) is a material with great interest in nanotechnology and with promising applications to biotechnology. Obtaining specific and regularly functionalized NAA surfaces is essential to obtain meaningful results and applications. Silane-PEG-NHS (triethoxysilane-polyethylene-glycol-N-hydroxysuccinimide) is a covalent linker commonly used for single-molecule studies. We investigate the functionalization of NAA with silane-PEG-NHS and compared with two common, but not single-molecule, grafting agents, APTMS (3-aminopropylotrimethoxysilane) as an electrostatic linker, and APTMS-GTA (3-aminopropylotrimethoxysilane-glutaraldehyde) as covalent. Another outcome of this study is to show how two proteins (collagen and bovine serum albumin, BSA) with different properties differentially arrange for different functionalizations and NAA pore sizes. FTIR is used to demonstrate the surface modification steps and fluorescence confocal microscopy reveals that silane-PEG-NHS results in a more homogeneous protein distribution in comparison to the other linkers. Reflection interference Fourier transform spectroscopy confirms the confocal fluorescence microscopy results and permits to estimate the amounts of linker and linked proteins within the pores. These results permit to obtain uniformly chemical modified NAA supports with a great value in biosensing, drug delivery and cell biology.
authors.affiliation: Departament d'Enginyeria Electrònica, Elèctrica i Automàtica, Universitat, Rovira i Virgili, Avda. Països Catalans 26, Tarragona 43007, Spain.
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Baranowska
authors.affiliation: Departament d'Enginyeria Electrònica, Elèctrica i Automàtica, Universitat, Rovira i Virgili, Avda. Països Catalans 26, Tarragona 43007, Spain.
authors.forename: Agata J
authors.initials: AJ
authors.lastname: Slota
authors.affiliation: Departament d'Enginyeria Electrònica, Elèctrica i Automàtica, Universitat, Rovira i Virgili, Avda. Països Catalans 26, Tarragona 43007, Spain.
authors.forename: Pinkie J
authors.initials: PJ
authors.lastname: Eravuchira
authors.affiliation: Departament d'Enginyeria Electrònica, Elèctrica i Automàtica, Universitat, Rovira i Virgili, Avda. Països Catalans 26, Tarragona 43007, Spain.
authors.forename: Gerard
authors.initials: G
authors.lastname: Macias
authors.affiliation: Departament d'Enginyeria Electrònica, Elèctrica i Automàtica, Universitat, Rovira i Virgili, Avda. Països Catalans 26, Tarragona 43007, Spain.
authors.forename: Elisabet
authors.initials: E
authors.lastname: Xifré-Pérez
authors.affiliation: Departament d'Enginyeria Electrònica, Elèctrica i Automàtica, Universitat, Rovira i Virgili, Avda. Països Catalans 26, Tarragona 43007, Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Pallares
authors.affiliation: Departament d'Enginyeria Electrònica, Elèctrica i Automàtica, Universitat, Rovira i Virgili, Avda. Països Catalans 26, Tarragona 43007, Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Ferré-Borrull
authors.affiliation: Departament d'Enginyeria Electrònica, Elèctrica i Automàtica, Universitat, Rovira i Virgili, Avda. Països Catalans 26, Tarragona 43007, Spain. Electronic address: lluis.marsal@urv.cat.
authors.forename: Lluís F
authors.initials: LF
authors.lastname: Marsal
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D001709:Biotechnology; D004566:Electrodes; D018613:Microscopy, Confocal; D058608:Nanopores; D011506:Proteins / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D011506:Proteins; D000537:Aluminum Oxide
keywords: BSA; Collagen; GTA; Nanoporous anodic alumina; Reflection interference Fourier transform spectroscopy (RIFTS); Silane-PEG-NHS