title: Computer simulations of the mechanical response of brushes on the surface of cancerous epithelial cells.
abstract: We report a model for atomic force microscopy by means of computer simulations of molecular brushes on surfaces of biological interest such as normal and cancerous cervical epithelial cells. Our model predicts that the force needed to produce a given indentation on brushes that can move on the surface of the cell (called "liquid" brushes) is the same as that required for brushes whose ends are fixed on the cell's surface (called "solid" brushes), as long as the tip of the microscope covers the entire area of the brush. Additionally, we find that cancerous cells are softer than normal ones, in agreement with various experiments. Moreover, soft brushes are found to display larger resistance to compression than stiff ones. This phenomenon is the consequence of the larger equilibrium length of the soft brushes and the cooperative association of solvent molecules trapped within the brushes, which leads to an increase in the osmotic pressure. Our results show that a careful characterization of the brushes on epithelial cells is indispensable when determining the mechanical response of cancerous cells.
authors: Instituto de Física, Universidad Autónoma de San Luis Potosí Álvaro Obregón 64, San Luis Potosí 78000, Mexico.
authors: A Gama
authors: AG
authors: Goicochea
authors: Departamento de Ciencias Naturales, Universidad Autónoma Metropolitana Unidad Cuajimalpa, Av. Vasco de Quiroga 4871, Distrito Federal 05300, Mexico.
authors: S J Alas
authors: SJ
authors: Guardado
mesh_terms: D001696:Biomechanical Phenomena; D003198:Computer Simulation; D004847:Epithelial Cells / Q000473:pathology*; D006801:Humans; D008954:Models, Biological; D009369:Neoplasms / Q000473:pathology*