IMAGING OF CELL WITH ATOMIC-FORCE MICROSCOPY OPERATED AT A TAPPING MODE

This paper reports direct imaging of cells with a new scanning mode fo r atomic force microscopy (AFM), a tapping mode for AFM (TMAFM). Two k inds of cells, Escherichia coli (E. coli) and cultured hamster ovary ( CHO) cells, prepared on indium tin oxide (ITO) glasses were observed i n air. The TMAFM yielded very reproducible images without appreciable modifications of the sample surfaces. The images were examined in two modes of the data representation; normal height-mode and deflection-mo de (similar to a first derivative of height-mode data) representations . The deflection-mode image of the E. coli sample showed much finer su rface details than the conventional height-mode one, while the height- mode image of the CHO sample provided more detailed structure than the deflection-mode one.