Although many bacterial species are vital to human health and are important in the food industry, some species lead to disease, which has promoted the development of antibacterial agents to reduce infection and illness. However, antibiotics can be toxic and increase bacterial resistance. Recently, we synthesized new silane-phosphonium monomers to form cross-linked thin coatings on polypropylene films. The produced silica-phosphonium coatings act as antibiofilm and antiviral agents. Here, we prepared and characterized poly-(silane-phosphonium) nanoparticles (NPs) by a modified Stöber polymerization process and characterized them by scanning electron microscopy (SEM), dynamic light scattering (DLS), zeta (ζ) potential, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared (FTIR) spectroscopy. These newly formed NPs illustrate great potential in inhibiting (), (), (), (), and the tomato brown rugose fruit virus (ToBRFV). These NPs are toxic to mammalian cells but may have potential use for a variety of agricultural, environmental, and medical applications, as discussed in the article.