Plasma Processing : Sanitation


Plasma-Enhanced Functionalization of Substrate Surfaces with Quaternary Ammonium and Phosphonium Groups

UW-Madison reseachers have developed a non-equilibrium, radio frequency plasma-enhanced approach for efficiently implanting antimicrobial functional groups on surfaces. A plasma treatment creates active sites directly on a substrate surface. Linker molecules are bound to the active sites, and quaternary ammonium precursor molecules are reacted with the linker molecules to result in anti-bacterial functional groups bound to the substrate surface. Alternatively, the active sites are exposed to a plasma of polymer precursor molecules, which are in turn reacted with quaternary phosphonium precursor molecules to generate the bactericidal groups. A third embodiment involves reacting polymer precursor molecules with linker molecules bound to the active sites. The polymers contain amine groups, which are converted to antimicrobial quarternary ammonium groups via alkylation.

Plasma-Aided Treatment of Surfaces Against Bacterial and Biofilm Deposition

UW-Madison researchers have developed a method for sterilizing the surfaces of such materials, and converting the contaminated deposits into inert, cross-linked films that are resistant to bacterial adhesion and attack. The process uses cold-plasma processing techniques. The material is exposed to an oxygen plasma discharge for a period of time sufficient to kill living bacterial cells and cross-link them to the material.