title: Understanding improved osteoblast behavior on select nanoporous anodic alumina.
abstract: The aim of this study was to prepare different sized porous anodic alumina (PAA) and examine preosteoblast (MC3T3-E1) attachment and proliferation on such nanoporous surfaces. In this study, PAA with tunable pore sizes (25 nm, 50 nm, and 75 nm) were fabricated by a two-step anodizing procedure in oxalic acid. The surface morphology and elemental composition of PAA were characterized by field emission scanning electron microscopy and X-ray photoelectron spectroscopy analysis. The nanopore arrays on all of the PAA samples were highly regular. X-ray photoelectron spectroscopy analysis suggested that the chemistry of PAA and flat aluminum surfaces were similar. However, contact angles were significantly greater on all of the PAA compared to flat aluminum substrates, which consequently altered protein adsorption profiles. The attachment and proliferation of preosteoblasts were determined for up to 7 days in culture using field emission scanning electron microscopy and a Cell Counting Kit-8. Results showed that nanoporous surfaces did not enhance initial preosteoblast attachment, whereas preosteoblast proliferation dramatically increased when the PAA pore size was either 50 nm or 75 nm compared to all other samples (P<0.05). Thus, this study showed that one can alter surface energy of aluminum by modifying surface nano-roughness alone (and not changing chemistry) through an anodization process to improve osteoblast density, and, thus, should be further studied as a bioactive interface for orthopedic applications.
authors.affiliation: College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, People's Republic of China.
authors.forename: Siyu
authors.initials: S
authors.lastname: Ni
authors.affiliation: College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, People's Republic of China.
authors.forename: Changyan
authors.initials: C
authors.lastname: Li
authors.affiliation: Department of Pathophysiology, Wenzhou Medical University, Wenzhou, People's Republic of China.
authors.forename: Shirong
authors.initials: S
authors.lastname: Ni
authors.affiliation: College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai, People's Republic of China.
authors.forename: Ting
authors.initials: T
authors.lastname: Chen
authors.affiliation: Department of Chemical Engineering, College of Engineering, Northeastern University, Boston, MA, USA ; Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Webster
mesh_terms: D000327:Adsorption; D000537:Aluminum Oxide / Q000737:chemistry* / Q000494:pharmacology*; D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D051379:Mice; D058608:Nanopores; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects*; D010316:Particle Size; D016062:Porosity
chemical_list: D000537:Aluminum Oxide
keywords: adhesion; nanostructure; orthopedics; preosteoblast; proliferation