Thermodynamic analysis of diatom Navicula pinna attachment to microtopographies

摘要

Biofouling formation on the surfaces of ship hulls can bring about some unwanted and detrimental consequences, which has been recognized as a widespread problem. Toxic compounds, such as copp er-based antifoulants, can prevent the happening of biological fouling, but they have negative impacts on non -target organisms and lead to detrimental ecological effects. Environmental concerns and legislation require developing new eco -friendly fouling -resistant technologies to replace toxic antifoulants. Recently, It was found that microtopographies of pillars, triangles/pillars, ridges and Sharklet AFTM could reduce the attachment of Ulva spores and Cobetia marina, and that hierarchical wrinkled surface topographies could resist biological fouling even after 18 months field test. It may be useful in the designing of more powerful antifouling microtopographies if we can correctly predict microbial adhesion on regular microstructures. In this paper, six well-defined microtopographies were applied to prevent N. pinna attachment, and thermodynamic method was used to predict cells adhesion. Diatom attachment assay showed that the cells density was reduced significantly on all microtopographies compared to the smooth surface, and the relative attachment density of N. pinna had a reciprocal -proportional relationship with the free energy of adhesion ( ΔGadh). Historical data also showed that the thermodynamic parameter ΔGadh is reliable to correctly predict Cobetia marina attachment to microtopographies, and the cell relative attachment density has a negative proportional correlation with ΔGadh too. Because thermodynamic approach can be used to calculate ΔGadh for cell attachment to regular and irregular surfaces, it may be widely used to design new antifouling materials.