We developed a cell sheet engineering platform based on poly(4-vinylpyridine) (P4VP) polymer brushes modified with metal nanoparticles (CuNPs) and evaluated their physicochemical properties and biocompatibility. The fabricated coatings exhibited antibiocidal activity and biocompatible characteristics, as well as thermoresponsive behavior, enabling temperature-dependent modulation of their properties.
The chemical composition and surface morphology of the coatings were characterized using atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Additionally, the release of CuNPs from the P4VP coatings was quantified through XPS.
The thermoresponsive nature of the coatings was verified by measuring water contact angles and collecting UV-Vis absorbance spectra as a function of temperature.
The antimicrobial properties of the CuNP-modified P4VP brushes were assessed through microbiological tests targeting contact- and release-based killing mechanisms, both of which demonstrated significant antibacterial efficacy.
To assess brushes’ biocompatibility, protein adsorption onto the polymer brushes was evaluated using immunofluorescence and immunochemistry assays. Furthermore, retinal pigment epithelium cells (ARPE-19 line) were cultured on the fabricated coatings, and cell viability was analyzed using the MTT assay. The results indicated sustained cell viability over time, suggesting biocompatibility of the coatings.
The thermoresponsive behavior of the P4VP brushes facilitated the spontaneous detachment of ARPE-19 cell sheets upon cooling. Post-detachment observations confirmed maintained viability of the released cells.
In conclusion, our study demonstrates the feasibility of creating biocompatible, thermoresponsive polymer coatings capable of spontaneous cell sheet detachment. These antibacterial, thermoresponsive coatings hold promise for applications in cell sheet engineering platforms for therapeutic purposes.
The study was funded by the “Research support module” as part of the “Excellence Initiative - Research University” program at the Jagiellonian University in Kraków (RSM/80/CA).
