Analysis of binding modes of biopanning heptapeptides with specific affinity to chitosan wrapped MSN

In this work, we demonstrated for the first time that six short heptapeptides screened out by biopanning strategy show affinity binding to chitosan wrapped mesoporous silica nanoparticle (CS/MSN). The interaction between peptide and chitosan-wrapped MSN (CS/MSN) was carefully analyzed with the aid of DLS and ELISA characterization. The results show that π-π stacking and hydrogen bonds account for the strong adsorption under neutral as well as acidic conditions. While hydrophilic and electrostatic interaction are the major modes of the peptide under alkaline condition. These different interaction modes involved in the adsorption of peptides onto CS/MSN could vividly mimic the binding of peptide with chitosan in physiological conditions and help to deeply understand the process of protein adsorption on nanomaterials.