We have studied synthesis and properties of ultrathin hydrogel coatings with a synthetic extracellular matrix (ECM) analogue: a chimeric peptide comprising a collagen-like peptide block Cys-Gly-(Pro-Lys-Gly)4 (Pro-Hyp-Gly)4 (Asp-Hyp-Gly)4- and the fibronectin RGD block -Arg-Gly-Asp-Ser-Pro-Gly (hereafter CLP-RGD) . For ultrathin hydrogel functionalized with the peptide, we employed initiator free, UV-controlled self-initiated photografting and photopolymerization reaction, on two different substrates: on glass  and medical grade PMMA plastic. In first step, the CLP-RGD peptide was functionalized via Michael addition reaction with methacrylate group using the 3-(acryloyloxy)-2-hydroxypropyl methacrylate reagent, thus obtaining a meathacrylate(MA)-Cys-CLP-RGD functional peptide. By combining MA-Cys-CLP-RGD, 2-hydroxyethyl methacrylate, PEG methacrylate and methacrylic acid monomers in self-initiated photografting and photopolymerization reaction we successfully synthesised 15-50 nm thick, mechanically stable ECM-mimetic peptide hydrogels. The hydrogel coatings were seeded with human skin fibroblast and human cornea epithelium cell lines, respectively. Both cell types formed monolayers on the hydrogel within 96 hours. Our study shows the potential of the fully synthetic ECM-like coatings for bioanalytical, tissue engineering and regenerative medicine application, especially applicable in the high throughput and biochip formats.
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