Calculation of the intracellular elastic modulus based on an atomic force microscope micro-cutting system

Abstract

Better understanding of variations in the mechanical properties of cancer cells could help to provide novel solutions for the diagnosis, prevention, and treatment of cancers. We therefore developed a calculation model of the intracellular elastic modulus based on the contact pressure between the silicon tip of an atomic force microscope and the target cells, and cutting depth. Ovarian cells (UACC-1598) and colon cancer cells (NCI-H716) were cut into sequential layers using an atomic force microscope silicon tip. The cutting area on the cells was 8 μm × 8 μm, and the loading force acting on the cells was increased from 17.523 to 32.126 μN. The elastic modulus distribution was measured after each cutting process. There were significant differences in contact pressure and cutting depth between different cells under the same loading force, which could be attributed to differences in their intrinsic structures and mechanical properties. The differences between the average elastic modulus and surface elastic modulus for UACC-1598 and NCI-H716 cells were 0.288±0.08 kPa and 0.376±0.16 kPa, respectively. These results demonstrate that this micro-cutting method can be used to measure intracellular mechanical properties, which could in turn provide a more accurate experimental basis for the development of novel methods for the diagnosis and treatment of various diseases.