The atomic force microscopy (AFM) images
of E. coli incubated in various toxic solutions were also
investigated. In order to evaluate the developed method
in comparison with other known measuring methods, we
chose three typical substances with toxicity data available
in the literature. Once the validity of the method is proven,
it can be extended to measure other substances even if
their toxicities are unknown. The proposed method, based
on our previous works (Liu et al., 2009a, 2009b), is very
simple and practical, and may be suitable for routine
control of food quality.