An antimicrobial composition and methods of use are provided. This antimicrobial composition includes a water-soluble organosilane (3-(trihydroxysilyl) propyldimethyloctadecyl ammonium chloride) and additional adjuvant compounds, including anti-inflammatory medications, antiseptics, transdermal penetrants, nutrients and/or buffers, generally to be applied in liquid form to penetrate and kill biofilms that are infecting living vertebrates. The methods include topically treating an infection by penetrating and disrupting an existing biofilm and killing cells therein and killing any persister cells that, through degrees of dormancy or otherwise, have escaped being killed during the initial application of the antimicrobial composition.
