RGD peptides micro-patterning on poly(ethylene terephthalate) surfaces

he aim of this study was to evaluate the impact of RGD micro-patterned poly(ethylene terephthalate) (PET) on human osteoblast progenitor (HOP) cells attachment. Biomimetic modifications were performed by means of a four-step reaction: surface hydrolysis, oxidation in order to create COOH functions, coupling agent grafting (EDC, NHS) and finally immobilization of peptides. In addition to homogeneous or statistically distribution of peptides, micro-patterns of RGD were generated by: optical photolithography and UV excimer laser ablation. Modification steps were validated by physico-chemical techniques: XPS was used to prove covalent grafting at each stage of the surface functionalization, toluidine blue assay and high resolution µ-imager (using [3H]-Lys) to evaluate peptide densities and validate micro-patterns formation. Finally, the efficiency of this biomodification of PET was demonstrated onto homogeneous surfaces by measuring the adhesion between 1 and 24 h of osteoprogenitor cells isolated from HBMSC