Investigation of human cellular response on cyclic RGD peptide immobilized on silicon surfaces via click chemistry

This study investigates the biological properties of cyclic RGD peptides being covalently immobilized via click chemistry onto alkyne terminated silicon surfaces.

At first cyclic RGD peptides were reacted with 4-azidophenyl isothiocyanate via a specific reaction. The azidated peptide was then covalently immobilized on an alkyne-terminated monolayer on silicon surfaces via the Cu (I)-catalyzed 1, 3-dipolarcycloaddition reaction. The surface structures of the attached peptide and control surfaces were characterized using X-ray photoelectron spectroscopy (XPS) and Fourier Transform Infrared (ATR-FTIR) Spectroscopy. Then after seeding human fibroblast cells on the peptide and control substrates, Scanning electron microscopy (SEM) and Laser scanning confocal microscopy (LSCM) was used to examine the morphology of human fibroblast cells. Adhesion and proliferation of human fibroblast cells on control and modified surfaces were analyzed by cell adhesion and (MTS) assay.

XPS and ATR-FTIR analysis showed the cyclic RGD peptides were successfully immobilized on silicon surfaces. Scanning electron microscopy (SEM) and Laser scanning confocal microscopy (LSCM) demonstrated that human fibroblast cells homogenously distributed across the peptide-modified substrates and had a uniform appearance. Peptide-modified surfaces exhibited substantially superior cellular responses compared to those on control surfaces.

The research may suggest a procedure for the fabrication of biologically active surfaces in biosensor platforms.