INTRODUCTION - Nanoindentation with Biological Applications - page 3

deformations. In addition to trying to gain fundamental physical
understanding, there are direct applications in fields such as medicine, an
example being the use of mechanical assays for diagnosis of disease.
In the context of human and medical applications, research on
mechanical functioning of biological materials is often labeled
“biomechanics”. The recent history of biomechanics extends back to
1452, with Leonardo da Vinci ( Fig. 1-1 ) in work that included
investigations at dominantly macroscopic length-scales, including the
description of whole-body motion, experiments on the mechanical
responses of organs and tissues, and the development of continuum-
based constitutive laws to describe tissue behavior. The pioneering
work of “the Father of Biomechanics,” Professor Y.C. Fung, 5,6 helped
establish the field as an autonomous scientific discipline within the
broader field of bioengineering.
Investigation of mechanical behavior of natural materials not
associated with human medicine is a field that has largely developed in
parallel to traditional (medically-oriented) biomechanics. These distinct
fields, however, have begun to merge as research has increasingly
focused on fundamental length-scales, as shown in Fig. 1-2 . The study of
natural materials—either in a medical or a basic science context—is
expanding with the application of modern materials characterization
techniques, many developed for probing materials and many for imaging
at the atomic and molecular scale, to the study of biological systems
( Fig. 1-2 ) . The introduction of materials science techniques to the study
of biomechanics has also been associated with the application of
materials science philosophy to biological problems: focus has shifted
subtly from purely mechanical explorations to investigations concerned
with structure-property relationships. New and developing subspecialties
have appeared including multi-scale theoretical modeling of hierarchical
biological structures, nanoindentation and nanotribology of biological
materials, nanomechanics of individual biological constituents, single
cell mechanics, and examination of bioadhesion and biolubrication.
The recent interest in studying mechanics of natural materials is
combined with a growing interest in biomimetic materials synthesis
for the creation of robust, and in many cases mechanically-functional,