The Mechanical Properties Bacteria by Atomic Force

Subject Areas :

Iraj Rezaei ^{1 *}

1 - Department of Mechanic, ET.C., Islamic Azad University, Tehran, Iran

Received: 2025-08-09 Accepted : 2025-10-16 Published : 2025-12-05

Keywords: Atomic Force Microscope, Bacteria, Elastic Modulus,

Abstract :

In this study, the mechanical properties of soft materials, including bacteria (Salmonella typhimurium and Listeria monocytogenes), have been investigated using nanoindentation by atomic force microscope (AFM), after obtaining the mechanical properties including the elasticity modulus and adhesion, the resonant frequencies and amplitude of the frequency response function (FRF) of the AFM beam’s vertical movements by considering the soft materials as the samples. Based on the obtained results, Salmonella typhimurium bacteria have the greater elastic modulus, but smaller adhesion than the monocytogenes bacteria. As a result of the increased elastic modulus, the resonant frequencies and amplitudes of the FRF of the AFM beam’s vertical movements increase. The results show good agreement between them. Based on the obtained results, Salmonella typhimurium bacteria have the greater elastic modulus, but smaller adhesion than the monocytogenes bacteria. As a result of the increased elastic modulus, the resonant frequencies and amplitudes of the FRF of the AFM beam’s vertical movements increase.

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