Antibacterial Activity of Superhydrophobic-SiO2 Coatings to Inhibit the Growth of Escherichia coli and Staphylococcus aureus

Abstract

The emergence of superhydrophobic antibacterial materials represents a promising approach to maintaining surface cleanliness and hygiene by effectively preventing bacterial adhesion. This research outlines the synthesis of a superhydrophobic coating with anti-adhesion and bacteriostatic properties, utilizing silica nanoparticles (SiO2 NPs) modified with 1H,1H,2H,2HPerfluorodecyltriethoxysilane (PFDTES). Transmission electron microscopy (TEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), and Fouriertransform infrared (FTIR) spectroscopy were conducted to analyze the coating’s morphology and surface characteristics. The coating was applied to glass substrates using the spray coating method, and the number of layers was varied to evaluate its antibacterial and bacteriostatic properties. These properties were measured using turbidimetry and inhibition halo techniques. Additionally, the durability of the coatings was assessed by exposing them to outdoor conditions for 35 days. This study aimed to evaluate the antibacterial and bacteriostatic capacities of the superhydrophobic coating, along with its resistance to outdoor weathering. The results indicate that a superhydrophobic coating with a contact angle ≥ 150◦ and a sliding angle ≤ 10◦ was successfully synthesized using SiO2 NPs smaller than 10 nm, modified with PFDTES. The coating demonstrated an ability to inhibit bacterial growth by preventing the adhesion of bacteria such as Escherichia coli and Staphylococcus aureus. Furthermore, the number of coating layers significantly influenced its bacteriostatic efficacy. The coating also exhibited strong durability under outdoor conditions. These findings highlight the potential application of superhydrophobic coatings for the prevention of bacterial adhesion and growth in environments where such contamination poses risks.