Understanding the interaction and adhesion of bacterial spores at surfaces—the first step for the subsequent germination—is very important in the fields of bioprocess engineering, medicine, and biological decontamination. Bacterial spore adhesion to inert surfaces is generally believed to involve surface hydrophobicity [1, 2], surface polarity [3], surface electrical charge [4, 5], and van der Waals (vdW) interactions.
Previously, we investigated the adhesion force between a Bacillus thuringiensis (Bt) spore and a gold planar surface using atomic force microscopy (AFM) measurements and calculations based on mechanistic modeling [6]. Although spores are known to attain electrostatic charge on their surface [7], previous experiments were conducted using a Bt spore and a gold substrate at conditions for which the electrostatic force could be ignored as a component of the adhesion force. Theoretical and experimental …