Development of Non-Invasive Deep Tissue pH Sensor

Tissue pH is a good indicator of the poor blood flow/poor oxygenation condition called ischemia, and can be used to assess tissue viability. Polestar Technologies, Inc. proposes a program to develop a non-invasive tissue pH sensor and monitoring system which utilizes the intrinsic light absorbing or emitting properties of pigments present in muscle and organ tissue. This Phase I effort proposes to evaluate two different optical methods for measuring tissue pH by collecting data from an animal model of ischemia. Optical signals from exposed muscle, as well as deep muscle tissue obscured by skin will be evaluated. Data collected by the non-invasive optical sensor will be correlated with pH measured by tissue pH electrodes to determine the most sensitive method for optically measuring pH and the appropriate wavelengths for use in the final sensor design. The goal of this project is to develop a conceptual design for a lightweight, portable, optical-based sensor and monitor capable of measuring pH for the assessment of tissue viability.