(Electro)chemically synthesis and characterization of new coating having N-halamines groups giving them regenerative antibacterial properties
Abstract
In the presence of moisture, surfaces are an ideal support for the
development of biofilms containing bacteria that can be pathogenic. This
poses a real public health problem, economic or even environmental in
view of the use of biocides to fight against this phenomenon. The first step
in the formation of a biofilm is the adsorption of molecules, especially
proteins, followed by the colonization of surfaces by bacteria.
The goal of this study is the development of new regenerative
antimicrobial coatings, containing haloamine (or N-halamine) functions(>
N-Cl or> N-Br) that have oxidative properties due to the degree of
oxidation +I (a,b). N-halamines are broad-spectrum biocidal groups; due to
their mode of action, i.e. oxidation, bacteria should not develop resistance,
unlike after repeated use of antiobiotics. The protection of surfaces with N-
halamine compounds requires the immobilization of amine, amide or imine
functions that will be transformed into haloamine either during synthesis
or by post-treatment in the presence of NaOCl or NaOBr.
In this study, we will present a new approach of gold surfaces
functionalization with the use of a biopolymer: polydopamine. The
synthesis of the polymer has been implemented with two original
approaches: a chemical and an electrochemical synthesis. We will present a
comparative study of both chemical and electrochemical polymerisation
and functionalization of gold surfaces characterized by means of PM-
RAIRS, XPS and (E)-QCM surfaces techniques. The control of the polymer
thickness shows a clear dependence of the antibacterial response with the
degree of chlorination or bromination. Finally, the simple regeneration of
the biocidal surfaces will be presented together with the biocidal activity
upon re-use of the surfaces