Multiscale Surface Topography of Hydrophilic Scallop Shells Is Associated with the Retention of Culturable Bacteria under Static and Dynamic Conditions

Abstract

Abstract When droplets carrying bacteria land on the medical device’s surface, they can cause contamination and promote biofilm formation. This study examined the impact behavior of droplets on five natural shell surfaces with varying hydrophilicity and surface texture, aiming to screen for surfaces that are both noncytotoxic and resistant to bacterial adhesion. Among these surfaces, the scallop surface exhibited the strongest resistance to bacterial adhesion and supported short-term BMSC attachment and viability, while the Babylonia shell surface showed the highest bacterial attachment. Notably, the most significant difference in antiadhesion performance between the scallop and the Babylonia shell occurred at low impact energy (We ≈ 16), where droplets neither rebounded nor splashed, yet the macro- and microscale structures on the scallop surface had already begun to interact effectively with the droplets. At higher Weber numbers, droplet impact dynamics may further enhance this resistance by generating local pressure gradients and shear forces, which may reduce bacterial retention on the surface, thereby amplifying the antiadhesion effect. Therefore, the superior antiadhesion of the scallop surface is associated with the synergistic action of its topography and droplet dynamics: its sharp nanoscale protrusions and high roughness may provide a foundational antiadhesion effect, while droplet impact dynamics may further amplify this effect. Notably, the scallop surface is not the most resistant in the nonimpact control, but performs best under dynamic impact, consistent with its topographical features being particularly responsive to hydrodynamic forces.

The authors' abstract, as published at the source. Langmuir, 2026 · DOI ↗