Improvement of the pore trapping method to immobilize vital coccoid bacteria for high-resolution AFM: a study of Staphylococcus aureus.

Preparation of vital bacteria for atomic force microscope study under aqueous fluid, such as physiological buffer or bacterial growth medium, presents challenges as cells will often desorb from the supporting surface or be dislodged by the atomic force microscope tip during imaging. An established method of immobilizing coccoid bacteria is to trap cells in polycarbonate track etched filter pores. We have significantly improved this method by modifying the pore diameter of commercially available filters to correspond to the diameter of the target strain, enabling high-resolution imaging of stationary organisms under buffer and dividing organisms under growth media.