Versatile gradients of chemistry, bound ligands and nanoparticles on alumina nanopore arrays

Abstract

Nanoporous alumina (PA) arrays produced by self-ordering growth, using electrochemical anodization, have been extensively explored for potential applications based upon the unique thermal, mechanical and structural properties, and high surface-to-volume ratio of these materials. However, the potential applications and functionality of these materials may be further extended by molecular-level engineering of the surface of the pore rims. In this paper we present a method for the generation of chemical gradients on the surface of PA arrays based upon plasma co-polymerization of two monomers. We further extend these chemical gradients, which are also gradients of surface charge, to those of bound ligands and number density gradients of nanoparticles. The latter represent a highly exotic new class of materials, comprising aligned PA, capped by gold nanoparticles around the rim of the pores. Gradients of chemistry, ligands and nanoparticles generated by our method retain the porous structure of the substrate, which is important in applications that take advantage of the inherent properties of these materials. This method can be readily extended to other porous materials.

Small surface nanotopography encourages fibroblast and osteoblast cell adhesion

“…S3 of the ESI 3 ). We aimed for a 5 nm thick polymer layer because previous work has shown that films prepared from allylamine are continuous 36,37 yet thin enough not to alter the magnitude of the surface nanotopography. To confirm this, cross sections of AFM images of surface immobilised 38 nm nanoparticles before and after deposition of the additional plasma polymer films were produced and are shown in the ESI 3 (Fig.…”

Surface Bound Amine Functional Group Density Influences Embryonic Stem Cell Maintenance

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pH-tunable gradients of wettability and surface potential

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