Novel Anti-Adhesive Biomaterial Patches: Preventing Biofilm with Metal Complex Films (MCF) Derived from a Microalgal Polysaccharide

Biofilm matrices formed by irreversibly surface-anchored bacteria cause significant economic damage in the industrial and biomedical environments. The ubiquity of biofilms promotes increased investment in the development of technologies that will impede bacteria-surface association. Certain surface topographical fabrications may aid in preventing colonization. Herein, algalsecreted polysaccharide (Ps) biomaterial patches and metal complex films (MCF) are examined for their anti-Acinetobacter baumannii and anti-Pseudomonas aeruginosa biofilm properties. Ps moderately reduces biofilm formation; the Cu-MCF coating has significant anti-biofim activity while Zn-MCF had no effect. A mechanistic examination of these effects shows a two-fold greater coverage of the anti-adhesive surface of Cu-MCF than that of the control due to the induction of swarming motility, thus impeding bacterial transformation to the irreversibly attached state. Chemical compositions of the coatings and the interactions between coating components are examined using X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectrometry. Cu-MCF surface morphology comprises protruding needle-like structures up to 100 nm in height that are lacking in both the Ps and the Zn-MCF. Their presence in an aqueous solution is yet unproven and role in preventing their bacterial attachment open to speculation. The present study highlights the need to generate novel biomaterials that integrate naturally occurring anti-adhesive polymers with specific metal ions to improve the chemical, physical and biological properties of these anti-adhesive surfaces. Cu-MCF complexes fabricated with thermal and pressure stability to prevent metal ion leakage hold promise for a broad spectrum of industrial and medical anti-biofilm applications.