(332a) Advanced Thin Film Polyampholyte Coatings to Prevent Bacteria Adhesion and Biofilm Formation in Microgravity

Bacteria adhesion and biofilm formation present significant challenges on Earth. These challenges are compounded in long duration space applications like the International Space Station (ISS) due to accessibility constraints. For example, bacteria isolates including Ralstonia (R.) picketti and Burkholderia (B.) cepacia have routinely been identified in samples returned from the water processing assembly (potable water) onboard the ISS. The utilization of nonfouling polyampholyte, mixed charge, thin film hydrogels offers a promising avenue for prevention of bacteria adhesion and biofilm formation as an alternative to remediation treatments. Preliminary experiments flown to the ISS in December 2021 demonstrated the promise of polyampholyte thin film coatings for preventing bacteria adhesion in microgravity. In this presentation, current research efforts focused on improving the bacteria resistance of [2-(acryloyloxy)ethyl] trimethylammonium chloride (TMA) and 2-carboxyethyl acrylate (CAA) thin film hydrogels on stainless steel will be presented. Results include optimizing the stainless-steel surface concentration of (3-acryloxypropyl) trichlorosilane, which is used to tether the thin film hydrogel to the surface, evaluating the impacts of a novel family of peptide-based zwitterionic cross-linkers, and correlating the coating thickness to performance. Both R. picketti and B. cepacian are being evaluated in gravity impacted and simulated microgravity conditions, in preparation for the Phase II evaluation on the ISS which will occur in the summer of 2024. The characterization of results from the Phase II microgravity experiment will also be presented.