The low Young's modulus of biological particles results in their large deformation against the AFM probe forces; therefore, it is necessary to study the contact mechanics of bioparticles in order to predict their mechanical behaviors. This paper specifically deals with the contact mechanics of DNA nanoparticles with spherical and cylindrical shapes during manipulation. In previous studies, these nanoparticles have been investigated in the elastic regime, which is not appropriate for biological particles. Therefore, in this paper, elastoplastic contact has been studied and compared with the other existing models. The contact regions have been analyzed by Hertz, JKR and Chang models for spherical contact and by Hertz and JKR models for cylindrical contact and compared with the FEM results. The results of this article indicate that JKR model is slightly different from the elastic simulation and that for the same magnitude of applied force, the
