High Resolution Laser Speckle Strain Gauge for Biomedical Research and Diagnostics

Oregon Health & Science University, Portland OR

Investigators

Abstract

0201841 Kirkpatrick The proposal focused on continued development and implementation of a high resolution, imaging laser speckle-based strain gauge for biomedical research and medical diagnostic purposes. During the period of this award, the investigators propose to expand the useful range of the system to the level of single cells and single-cell thick cell layers and to develop and implement an optical means by which the viscoelastic properties of tissues and cell sheets can be measured directly in a nondestructive manner. The hypotheses driving this research are: 1) Improved laser speckle strain measurement technology can provide detailed information on the mechanical behavior of tissues at the cellular level with better strain resolution than strain technologies conventionally employed for these purposes, including classical interferometric technologies, 2) Variations of the speckle strain gauge can yield information regarding the viscoelastic constants of biological tissues such as mechanical loss factor (tan d), storage modulus, and loss modulus and 3) The strain gauge technology can be modified to provide full 2D strain data of tissues under biaxial loading. The specific aims to test these hypotheses are: 1) To implement an imaging laser speckle strain gauge for evaluating the micromechanical behavior of single-cells and cell sheets, 2) To develop a variation of the speckle strain gauge to yield viscoelastic constants such as loss factor (tan d), storage modulus and loss modulus and 3) To modify the speckle strain gauge to acquire and analyze 2-dimensional strain data. Results of the studies should have a significant impact on a variety of modern diagnostic and therapeutic applications.