Potential roles of fluorine-containing sol-gel coatings against adhesion to control microbial biofilm

Treatment of materials by sol-gel technique can be an excellent tool to convey new properties to surfaces, therefore the hybrid organic-inorganic materials show the properties of both phases, contributing for example to the obtainment of an anti-fouling coating. In this research, the explored procedure includes the co-condensation of silane coupling agents with epoxide and amine tail-groups, (3-Glycidyloxypropyl)-trimethoxysilane (GPTMS) and (3- Aminopropyl)-triethoxysilane (APTES), respectively, in combination with two perfluorosilane precursors, namely glycidyl-2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9-hexadecafluorononylether and trimethoxy-(3,3,3-trifluoropropyl)-silane, either individually or together. This synthetic approach allows collecting stable hydrophobic, non-toxic, anti-fouling coatings that were investigated to study their morphology and chemical structure by different physical-chemical techniques. The anti-fouling properties were evaluated through test on treated glass slides in different microbial suspension in seawater-based medium per 24 h at room temperature. During tests, each suspension was maintained in continuous agitation to simulate the natural movement of seawater, and the attachment of cells on bare degreased glass slides is compared with that occurring on the treated slides. Results show that the fluorinated coatings have good antimicrobial activities and low adhesive properties, no biocidal effects towards the studied microorganisms were observed.