Influence of Low-Voltage Alternating Electric Fields on the Formation of Conditional Films in Marine Environments

Marine biofouling begins with the adsorption of organic macromolecules derived from seawater onto the surfaces of materials, forming conditioning films that facilitate the subsequent attachment of fouling microorganisms such as diatoms. In this study, we used BSA and sodium alginate as model organic components to investigate the effect of low-voltage alternating electric fields on the formation of conditioning films on the surfaces of TC4 titanium alloy and 316 stainless steel. Infrared spectroscopy and contact angle analysis confirmed the successful preparation of the conditioning films. The phenol-sulfuric acid method and the BCA protein assay were used to quantify the changes in the contents of alginate and BSA. The optimal suppression (the surface of the titanium alloy was 90%, and that on the surface of the stainless steel was 98%) occurred at 1.8 kHz and 0.5 V. The hydrophilicity of the titanium alloy surface increased by approximately 34.5%, and the hydrophilicity of the stainless steel surface increased by approximately 41.0%. Notably, Zeta potential measurements showed that both BSA and alginate carried negative charges, indicating that the electric field oscillations induced by the alternating electric fields could drive their periodic movement, thereby inhibiting the adhesion of the conditioning films.