Chemical reactions directed peptide self-assembly

Abstract

In recent years, significant efforts have been made to develop functional materials in the field of nanoscience and biomedicine. Self-assembly is a prevalent process in nature and has exhibited great advantages in the development of functional architectures. Low molecular weight organic compounds are routinely being used in the construction of self-assembled nanostructures. Self-assembly of small peptides have attracted considerable attention due to their potential applications in tissue engineering, cell culture, drug delivery and biosensing. Peptide selfassembly is driven by various non-covalent interactions including hydrogen bonding, π- stacking and hydrophobic interactions. To date, a number of stimuli have been used in the development of peptide selfassembly. Still, there is wide interest to develop novel biocompatible approaches for the fabrication of self-assembled soft materials and their further applications in biomedicine. The main objectives of present study are:  To synthesise small Nmoc-protected (Nmoc = Naphthalene-2- methoxycarbonyl) peptides and to study their self-assembly processes by novel approaches.  Native chemical ligation is the most widely used method in protein synthesis. To achieve simple and efficient method for peptide selfassembly, our intention was to exploit oxo-ester mediated native chemical ligation in peptide coupling and subsequent formation of self-assembled peptide nanostructures.  To develop a simple and easy orthogonal approach for peptide coupling and self-assembly process. We opted to synthesise Nmocprotected- selenoesters which can readily undergo NCL reactions with N-terminal cysteine and cysteine based peptides. To exploit enzymatic peptide hydrolysis reaction in order to achieve a single predominating product from the dynamic peptide libraries via self-assembly.  To study lipase catalyzed esterification reaction of Nmoc-protected peptides with gastrodigenin p-hydroxybenzyl alcohol in aqueous medium at physiological pH for the development of blue light emitting biomaterials.