Impact of Ag-SiO₂ Nanocomposite on Metal Corrosive Desulfovibrio Biofilm

Microbiologically influenced corrosion (MIC) is a significant issue causing material damage of metals in pipelines, storage tanks, and marine infrastructure, leading to significant industrial damage and maintenance costs. Anaerobic sulfate-reducing bacteria (SRB) are the main causative agent for MIC. Their capacity to form biofilms facilitates SRB to cause high corrosion rates. In this study, Ag-SiO₂ nanocomposite with silver nanoparticle (Ag NP) dispersed in the silicon dioxide (SiO₂) matrix was synthesized using a one-pot sol-gel method. Ag-SiO₂ NC was evaluated for its capacity to deter biofilm formation and impact the transcript gene expression of key markers HydA and DVU1817 Cytochrome c553 genes for the SRB biofilm-formation and metal corrosion in Desulphovibrio gigas strain. The effect of Ag-SiO₂ NC on the SRB mediated Carbon steel corrosion was also examined using potentiodynamic polarization electrochemical corrosion testing. The findings from our study validate the antibacterial and corrosion inhibitory characteristics of nanocomposite Ag-SiO₂ NC against D. gigas. A simple and reproducible Ag-SiO₂ NC synthesis will significantly boost the industrial production of silver-doped silica products for controlling SRB population, enabling development of advanced high-performance protective metal coatings with enhanced antimicrobial properties.