PD Dr. Ulrike Ritz (Mainz, DE), Kira Vogel (Mainz, DE), Karl Schönewald (Mainz, DE), Fiona Diehl (Siegen, DE), Jutta Goldschmidt (Mainz, DE), Christina Babel (Mainz, DE), Prof. Dr. Peer Kämmerer (Mainz, DE), Ulrich Jonas (Siegen, DE)
Abstract text (incl. figure legends and references)
Short-term implants are widely used to achieve a temporary support function of the bone apparatus. For these implants it is desirable that the implants do not bond with the surrounding tissue and the bone itself in order to prevent surgical complications as well as ruptures during removal. An anti-adhesive and antibacterial coating could reduce complications associated with metal removal and reduce the risk of infection.
Macromolecular hydrogels present modularly combinable monomers, producing biocompatible, anti-adhesive and antibacterial polymer networks, which can be bonded to different (implant) surfaces. We developed a two-component hydrogel based on (1) an adhesion polymer consisting of acrylamide-based, hydrophilic main monomers and phosphonic acid derivatives and (2) a crosslinkable prepolymer consisting of acrylamide-based, hydrophilic main monomers and benzophenone derivatives as crosslinkers. Cytotoxicity tests (DIN ISO 10993-5) confirmed biocompatibility of the polymers.
Primary fibroblasts or tenocytes were seeded on cell culture plates and titanium discs partially coated with polymer. The figure shows that the cells grow exclusively on the uncoated part of the cell culture plate. Also, no cell adhesion occured on the titanium surface coated with polymer. Non-adherent cells were vital, as they adhered and proliferated after transfer to an uncoated titanium plate.
The bacterium mainly responsible for infections in the bone osteosynthesis area is Staphylococcus aureus. This bacterial strain was applied diluted in medium on the layers and after 24 h the medium was seeded in different dilutions on agar plates. No CFUs (colony forming units) were detected on the sample incubated on a plate coated with an antibacterial polymer, indicating a clear antimicrobial effect of the polymers.
In conclusion, the coatings successfully prevented adhesion of primary cells and inhibited bacterial growth, making them interesting for use on short-term implants.