Non-covalent Interaction of Tryptophan with Functional Monomers in Self-assembly Systems

Abstract

The non-covalent interaction of tryptophan(L-Trp) with adipic dihydrazide(ADH),diacetone acrylamide(DAAM) or acrylic acid(AA) was investigated by fluorescence quenching,three-dimensional fluorescence spectrum in combination with computer simulation,respectively.The quenching mechanism,the strength and types of interaction force between L-Trp and functional monomers were studied.The results showed that the fluorescence of L-Trp was quenched through a static quenching procedure by functional monomer due to the formation of L-Trp-functional monomer complexes.The complexes had high binding constant and exhibited good stability.The non-covalent interaction between L-Trp and functional monomers was dominated by hydrogen bond and electrostatic force.The binding site in L-Trp was supplied largely by carboxyl group rather than heteroaromatic ring.The strength of interaction between L-Trp and functional monomers was in the following order: L-Trp-ADHL-Trp-DAAML-Trp-AA.