A research team from the Institute of Physics of the Czech Academy of Sciences, led by Hana Lísalová from the Laboratory of Functional Biointerfaces (LFB) of the Division of Optics, has developed a new polymeric nanocoating. It effectively prevents the accumulation of proteins and bacteria on the surface of biomaterials while promoting desirable immune cell responses and supporting the growth of bone-forming cells. The project was made possible thanks to the dedication of PhD student Alina Schleichert from LFB, who initiated collaboration with the top research group of Erik Reimhult at Austria’s BOKU University as part of her mobility activities. The results were published in the prestigious journal ACS Applied Materials & Interfaces.
The newly developed terpolymer combines three building blocks: the zwitterionic CBMAA, which enables the attachment of bioactive molecules thanks to reactive carboxyl groups; the zwitterionic SBMAA for maintaining stable and balanced surface charge; and the nonionic, highly hydrophilic HPMAA, which ensures strong hydration of the coating. This combination allows the surface to be tuned between maximizing the repulsion of unwanted proteins and bacteria and the targeted promotion of adhesion (and growth) of selected cell types.
“Our goal was to design a surface that not only serves as a passive protective shield, but also actively interacts with the biological environment,” explains Hana Lísalová, head of the Laboratory of Functional Biointerfaces. “We are seeing that a carefully selected combination of polymer components can significantly reduce protein and bacterial deposition without interfering with natural cellular processes.”
The optimized coating composition reduced protein adsorption by up to 98% even in serum-rich environments and simultaneously decreased the adhesion of common pathogenic bacteria by more than 99%. As a result, it greatly lowers the risk of bacterial biofilm formation, a frequent cause of malfunction in biomaterials and medical devices.
The study also demonstrated that the surface equipped with this polymer brush positively influences the behavior of macrophages, key immune system cells. They remain mobile on the surface and efficiently engulf bacteria without excessively adhering to the material or triggering unwanted inflammatory responses.
Another advantage of the coating is its functional adaptability. Through subsequent chemical modification, bioactive molecules—such as RGD peptides that promote the adhesion and proliferation of osteoblasts—can be attached to the polymer layer. This makes the coating suitable both for temporary medical devices where minimal cell interaction is desirable, and for permanent implants that require strong integration with tissue.
“This research is a textbook example of how physical and chemical principles can be connected with real biomedical applications,” adds Alexandr Dejneka, head of the Division of Optics at the Institute of Physics CAS. “The ability to precisely control interactions at the material–biological interface is essential not only for the development of biomaterials, but also for biosensors and other optical systems where long-term surface stability is critical.”
The work shows that carefully engineered polymer nanolayers can combine seemingly contradictory properties—strong antifouling protection and support for biologically beneficial processes. Such materials have the potential to substantially advance the development of safer and more functional implants and other biomedical technologies.
The study was made possible through research stays supported by the FZU Researchers, Technical and Administrative Staff Mobility program and the Ernst Mach Grant, which enabled targeted integration of experimental approaches between the Institute of Physics of the Czech Academy of Sciences and Vienna’s BOKU University. It was also supported by the SENDISO project within the Jan Ámos Komenský Operational Programme.