Chemical Force Microscopy of Single Live Cells

Abstract

Traditionally, cell surface properties have been difficult to study at the subcellular level, especially on hydrated, live cells. Here, we demonstrate the ability of chemical force microscopy to map the hydrophobicity of single live cells with nanoscale resolution. After validating the technique on reference surfaces with known chemistry, we probe the local hydrophobic character of two medically important microorganisms, Aspergillus fumigatus and Mycobacterium bovis, in relation with function. Applicable to a wide variety of cells, the chemically sensitive imaging method presented here provides new opportunities for studying the nanoscale surface properties of live cells and for understanding their roles in mediating cellular events.

Surface Structure Characterization of Aspergillus fumigatus Conidia Mutated in the Melanin Synthesis Pathway and Their Human Cellular Immune Response

“…Three-dimensional images are generated in buffer by scanning a sharp tip over the cell surface while sensing the interaction force between the tip and the surface. Originally invented for topographic imaging, AFM has evolved into a multifunctional molecular toolkit, enabling researchers not only to observe structural details of cells to near molecular resolution (36,38) but also to measure their biophysical properties and interac- tions (39)(40)(41). In contrast to the WT conidia that are covered with rodlet structure (30,42) (Fig.…”

High-speed atomic force microscopy coming of age

“…However, the mechanism and dynamics of fibrillization have been elusive. Lithosthatine (also named Reg-1) of 144 amino acids is produced 23 by pancreas acinar cells and secreted into pancreatic juice. It tightly binds calcium carbonate and may act as an inhibitor of calcium carbonate precipitation to prevent clogging of pancreatic duct [177,178].…”

High-Speed AFM and Applications to Biomolecular Systems

“…In biological sciences, this microscopy is now routinely used to directly acquire high-resolution images of biological samples under physiological conditions, without sample staining (66,81,82). AFM is also used for the recognition and localization of specific molecules (37, 91) as well as force measurements to estimate the strength of intra-and intermolecular bonds at the single-molecule level (26,67,108), the elasticity of biological surfaces (19,98), and the osmotic pressure of live cells (90). Therefore, AFM is a nano-toolbox for biology (reviewed in References 64 and 65).…”