title: Multifunctional substrates of thin porous alumina for cell biosensors.
abstract: We have fabricated anodic porous alumina from thin films (100/500 nm) of aluminium deposited on technological substrates of silicon/glass, and investigated the feasibility of this material as a surface for the development of analytical biosensors aiming to assess the status of living cells. To this goal, porous alumina surfaces with fixed pitch and variable pore size were analyzed for various functionalities. Gold coated (about 25 nm) alumina revealed surface enhanced Raman scattering increasing with the decrease in wall thickness, with factor up to values of approximately 10(4) with respect to the flat gold surface. Bare porous alumina was employed for micro-patterning and observation via fluorescence images of dye molecules, which demonstrated the surface capability for a drug-loading device. NIH-3T3 fibroblast cells were cultured in vitro and examined after 2 days since seeding, and no significant (P > 0.05) differences in their proliferation were observed on porous and non-porous materials. The effect on cell cultures of pore size in the range of 50-130 nm--with pore pitch of about 250 nm--showed no significant differences in cell viability and similar levels in all cases as on a control substrate. Future work will address combination of all above capabilities into a single device.
authors.affiliation: Nanophysics, Istituto Italiano di Tecnologia, via Morego 30, 16163, Genoa, Italy, chiara.toccafondi@iit.it.
authors.forename: Chiara
authors.initials: C
authors.lastname: Toccafondi
authors.forename: Sanjay
authors.initials: S
authors.lastname: Thorat
authors.forename: Rosanna
authors.initials: R
authors.lastname: La Rocca
authors.forename: Alice
authors.initials: A
authors.lastname: Scarpellini
authors.forename: Marco
authors.initials: M
authors.lastname: Salerno
authors.forename: Silvia
authors.initials: S
authors.lastname: Dante
authors.forename: Gobind
authors.initials: G
authors.lastname: Das
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods; D002448:Cell Adhesion; D018929:Cell Culture Techniques / Q000295:instrumentation*; D002470:Cell Survival / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D005240:Feasibility Studies; D006046:Gold / Q000737:chemistry; D008422:Materials Testing; D051379:Mice; D041681:NIH 3T3 Cells; D049329:Nanostructures / Q000737:chemistry; D016062:Porosity; D013499:Surface Properties
chemical_list: D020099:Coated Materials, Biocompatible; D006046:Gold; D000537:Aluminum Oxide