Spatiotemporally Controlled Formation of Two-Component Counterpropagating Lateral Graft Density Gradients of Mixed Polymer Brushes on Planar Au Surfaces

摘要

In the past several years there has been a great deal of interest in generating and utilizing gradient surfaces because of their potential use in a large number of applications, for example as substrates for selective adsorption, templates for cell adhesion and cell migration, and tools for combinatorial chemistry studies. A number of techniques to generate gradients on various substrates have been reported, including diffusion-controlled vapor deposition, cross diffusion, corona discharge, photoimmobilization,' electrochemical-potential gradients, the use of microfluidic devices, and, more recently, surface-initiated polymerization through atom-transfer radical polymerization (ATRP).