One of the major challenges for modern implantology is the avoidance of implant failure and minimization of revisions and follow-up procedures for patients. For successful implant integration without future adverse effects, bacterial colonization of the implant-tissue-interface and the formation of a biofilm specifically needs to be avoided. [1,2]
One way of resolving this issue is the utilization of quaternized ammonium cations (QACs) on the surface that exhibit bacteria killing properties. [3] Once the bacteria have been killed however, bacterial debris piles up on the charged surface; effectively rendering the surface incapable of fulfilling its purpose for extended periods of time which is an issue in implantology. [4] Making use of zwitterionic moieties within the same active surface introduces a possibility to get rid of such debris due to its inherent anti-fouling properties. [5] Depending on the salt concentration of the environment, either the cationic or the zwitterionic portion of the compound becomes active (Fig. 1). Moreover, making use of the high biocompatibility of a hydrogel should greatly improve its performance in real-world applications.
So for this work, the synthesis and characterization of such switchable polyelectrolyte compounds is being carried out as well as their integration into a polymeric backbone, giving access to simple, dip-coatable network precursors that yield their respective hydrogels by UV-irradiation. Additionally, monomers with varying spacer lengths have been synthesized to alter the amphiphilic balance and directly influence the antibacterial activity.