Modeling and analysis of nanoscale interaction forces between Acidithiobacillus ferrooxidans and AFM tip

The specificity exhibited by Acidithiobacillus ferrooxidans, a chemolithoautotrophic acidophile, in their attachment to different sulphide minerals has resulted in effective physical separation of these minerals. This can be explained in terms of surface forces of interaction between the cells and substrates using AFM. In the light of this, the present study reports interaction studies with A. ferrooxidans cells and an AFM silicon nitride tip. The aim of the present investigation is to probe the nanoscale interactions between A. ferrooxidans cells and silicon nitride tip of an AFM, model the approach and retraction forces, and elucidate the effects of pH, ionic strength and surface biopolymers on interfacial forces.