NANO-, BIO- MECHANICS

Vinu Unnikrishnan, Ginu Unnikrishnan and J. N. Reddy

Biological materials are complex multiscale systems. The emphasis on the computational modeling of the biological systems is to gain fundamental understanding of the behavior of these systems under ex-vivo and in-vivo conditions and improve the diagnostic and treatment tools currently used in clinical practice. The multiscale nature of the biological materials necessitates a multiscale computational model.

Cell Mechanics: The basis of the study was the need sound mathematical and computational framework to understand mechanical behavior of cell. Using the homogenization scheme of Mori-Tanaka, the effective material properties of a mixture of cytoplasm and stress fibers are obtained. This homogenized material property is incorporated into the finite element models of cell, along with the material property of nucleus, to determine the mechanical behavior of cell to an external loading condition.

RE10-FIG1

Simulation of AFM indentation using material property obtained from continuum micromechanics

Fluid-porous interface model

Fluid-porous (F-P) interface model was developed and applied in physiological occurrences of fluid-tissue interfaces as in blood flow through artery. One such example is the arterial block caused by the deposition of Low density lipoproteins (LDL) on the arterial wall. By understanding how the proteins are being deposited on the arterial wall we can understand the changes in the arterial flow patterns at the macroscale. Such information could be used for diagnosis of atherosclerosis. At the region of stenosis (block), a sharp decrease in the pressure was observed, even going to the range of negative values, followed by a recovery at the post-stenotic region. The decrease in pressure is also observed to increase with stenosis severity.

RE10-FIG2

Blood flow through constricted artery

Nanocomposites for tissue engineering

Tissue engineering, which aims to repair, restore living tissues using biomaterials, cells and engineering principles, individually or in combination, has emerged as an alternative, promising strategy for the development of viable substitutes for cardiovascular tissues. In tissue engineering, bioreactors play a very important role as they provide the necessary physiological and mechanical environment for the development of scaffolds. In this research, a computational model that can provide accurate determination of mechanical environment within the bioreactor using fluid-biphasic finite element method is implemented to study the influence of scaffold material properties on the distribution of mechanical environment within the bioreactor.

RE10-FIG3

Nanocomposite for tissue engineering applications