Analysis of cells elasticity based on force-distance curves obtained from atomic force microscopy

Automated techniques for measuring elasticity parameters of cells enable development of new diagnosis methods. An important elasticity parameter is the Young’s modulus (YM), which has been effectively used to characterize different cell properties, e. g., platelet activation, locomotion, differentiation, and aging. This paper deals with the problem of automated determination of cells YM based on the force-distance curves obtained from atomic force microscope. During experiments, the YM of cells was determined by using contact point detection and curve fitting algorithms. Experimental results were compared for two theoretical models of indentation: Hertz model, and Sneddon model. The results show that single indentation model allows a satisfactory accuracy to be obtained only for a subset of the force-distance curves. The most appropriate model for a given curve can be selected based on the fitting error analysis.