Anisotropic three-dimensional peptide channels guide neurite outgrowth within a biodegradable hydrogel matrix

Abstract
The objective of this study was to investigate the neurite guidance potential of concentration gradients of glycine-arginine-glycine-aspartic acid-serine (GRGDS) oligopeptides immobilized within three-dimensional patterned cylindrical volumes created in a biodegradable nerve guidance matrix. This was achieved using ultraviolet (UV) laser micropatterning of a hyaluronan (HA) hydrogel matrix modified with S-2-nitrobenzyl cysteine. Upon exposure to focused laser light, the 2-nitrobenzyl group was cleaved, exposing thiol groups which reacted with maleimide-terminated GRGDS exclusively within these laser-defined volumes. We show that the UV laser micropatterning technique can be used to create GRGDS peptide concentration gradients within the oligopeptide channels and that these channels guide neurite outgrowth from primary neural cells.