UC Irvine

This dissertation addresses the challenges associated with electrophysiological research in small animal models, such as rodents, amphibians, and zebrafish, by developing and implementing miniaturized, wearable, and non-invasive biosensors. Existing methods are limited by factors like invasiveness, interference with normal activities, and potential discomfort. By refining and miniaturizing these devices using advancements in microelectromechanical systems (MEMS) technology and the electronics industry, this research seeks to improve the welfare of the animals involved, enhance the accuracy of the data collected, and broaden the applications of electrophysiological research in biology, ecology, and human health. The integration of supplementary sensors, including wearable pH sensors, high-precision tracking and location systems, and potentiostats for in vivo monitoring of metabolic substrates, allows for a more comprehensive understanding of the complex relationships between animals and their environment. A significant contribution of this research is the development of stability-enhanced iridium oxide-based pH sensors, which offer improved accuracy and reliability for environmental assessment, particularly in aquatic environments. Additionally, the integration of wireless power and data transmission methods streamlines the design of these integrated systems, enhancing their convenience and user-friendliness. The dissertation is organized into sections covering a comprehensive literature review, analysis of several animal models, detailed examination of an unconventional animal model (Xenopus laevis), introduction of the developed devices, presentation of results highlighting their effectiveness, and exploration of future research directions. Through this in-depth examination, the dissertation contributes to the advancement of knowledge in electrophysiological research involving small animal models, providing valuable insights into the intricate interactions between animals and their environment, as well as their physiological adaptations in response to various stressors.