Chitosan-zinc oxide nanocomposite coatings prevent marine biofouling
Global concerns about the high toxicity of antifouling paints have highlighted the need to develop less toxic antifouling coatings. In a study, researchers tested the antifouling activity of chitosan-ZnO nanocomposite hybrid coatings.
Chitosan is a natural polymer with antimicrobial, antifungal and antialgal properties that is obtained from partial deacetylation of crustacean waste.
High antidiatom and anti-bacterial activity
Chitosan-ZnO nanoparticle coatings showed anti-diatom activity against Navicula sp. and antibacterial activity against the marine bacterium Pseudoalteromonas nigrifaciens. Additional antifouling properties of the coatings were investigated in a mesocosm study using tanks containing natural sea water under controlled laboratory conditions. Each week for four weeks, biofilm was removed and analysed by flow cytometry to estimate total bacterial densities on the coated substrates. Chitosan-ZnO hybrid coatings led to better inhibition of bacterial growth in comparison to chitosan coatings alone, as determined by flow cytometry. This study demonstrates the antifouling potential of chitosan-ZnO nanocomposite hybrid coatings, which can be used for the prevention of biofouling.
The study is published in: Chemosphere, Volume 168, February 2017, Pages 408–417.
