Nanoscale hydrophilicity studies of Gulf parrotfish (Scarus persicus) scales.

The Gulf parrotfish (Scarus persicus) offers inspiration for a strategy to combat marine biofouling, a problem of great economic and environmental interest to the maritime community, through its use of a continually maintained, multifunctional, water-based mucus layer to cover its scales. In this study, to better understand the scale-mucus interface, we investigate the nanoscale hydrophilicity of the fish scales by comparing reconstructed force distance profiles obtained using an amplitude-modulation atomic force microscopy (AM-AFM) technique. We note significant differences between three morphologically distinct regions of each scale, as well as between scales from four spatially distinct regions of the fish. This study reveals a previously unreported property of fish scales and proves the value of a new AFM technique to the field of biomaterials.