Design of peptide-PEG-Thiazole bound polypyrrole supramolecular assemblies for enhanced neuronal cell interactions

Abstract

ABSTRACT Brain injuries, and neurodegenerative diseases can result in significant disability, lowered quality of life, and mortality. Current treatments including autologous nerve grafts are insufficient. This work presents the creation of new biomimetic supramolecular assemblies as a scaffold for potential applications in neural tissue regeneration. It is composed of polyethylene glycol amide core-conjugated with a thiazole-based building block and a peptide sequence (RVYNMGKGKGFCVPRPLVVYR). This peptide sequence is derived from laminin, a basal membrane protein, and a component of the extracellular matrix of neuronal cells. The product formed was allowed to self-assemble and bound to polypyrrole by layer-by-layer assembly to impart conductive properties (Lam-PEG-thiazole-PPy) resulting in the formation of fibrillar assemblies as indicated by electron microscopy studies. Rheological studies demonstrated that incorporation of PPy resulted in higher storage modulus indicative of higher ability to store deformation energy. Culture of rat olfactory-bulb derived neurons with the assemblies demonstrated that the Lam-PEG-thiazole-PPy assemblies promoted cell proliferation and were able to interact favorably with the cells. After 10 days of culture with the assemblies interconnected networks could be visualized. Furthermore, electrical stimulation resulted in a significant increase in axonal outgrowths. Thus, the assemblies presented herein exhibit potential for applications as a novel scaffold for neural tissue engineering.