Evaluation of anti-microfouling activity of marine paints by microscopical techniques

The use of two microscopical techniques, SEM and CLSM, was investigated to facilitate the observation of adhered microfouling on antifouling paints. Bacterial and diatom colonisation was quantified on antifouling paints and compared with the standard test, ASTM D 3623. The results indicate that there is a likely correlation between the microscopic study and the antifouling activity. The study revealed the interest of CLSM for the evaluation of antifouling paints and reports on the efficacy of CLSM to study the initial microfouling layer. This method can yield important data relating to biofilm morphology, particularly film thickness and biomass measurements. This non-invasive technique enabled us to obtain qualitative and quantitative data about the biofilm formation during the first weeks of immersion in seawater.

► A correlation exists between the microscopic study and the antifouling activity.
► The efficacy of CLSM to study the initial microfouling layer has been demonstrated.
► Quantitative data about the biofilm formation in seawater has been obtained.