Development of Micro-actuators and Micro-sensors for the On-chip Interrogation of Cells and In Vitro Generated Tissues.

Microscale systems for improved invitro cell culture platforms;Biomedical Engineering;Engineering;Biomedical Engineering

Lesher-Perez, Sasha CaiBurns, Mark A. ;

University of Michigan

关键词: Microscale systems for improved invitro cell culture platforms;    Biomedical Engineering;    Engineering;    Biomedical Engineering;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/113506/sashacai_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Microscale systems enable interrogation of biological mechanisms beyond the capacity of conventional macroscale techniques. The large surface-to-volume ratio of microscale platforms allows investigators to better control the spatial and temporal microenvironment presented to biological samples, manipulating samples at scales reminiscent of their native microenvironments. This research describes microscale technologies to advance the design, complexity, and control of tissue culture microenvironments in three areas – chemical stimulation, regulating cell culture dimensionality, and oxygen monitoring. These tools improve in vitro models to better emulate the native biological response. To regulate temporal patterns of biochemical stimulation I developed an autonomous microfluidic oscillator circuit that enables dynamic control of delivered fluids without external control signals. This work produced to (1) a practical system to modulate the duty cycle of an applied stimulus in a user-defined manner without requiring modification of the device itself; and (2) a method to couple multiple independent oscillators together to ensure uniformity of experimental parameters, such as frequency and duty cycle, across multiple devices. In other work, reproducibility of three-dimensional spheroid cultures was achieved by culture additives to generate increasingly complex, and robust microscale cultures. We also developed dispersible microsensors for tissue culture oxygen measurements. When recreating physiologic microenvironments, it is critical to monitor and quantify the presence of oxygen. The untethered biocompatible oxygen sensors can be embedded or dispersed within diverse culture conditions for the real-time/continuous detection of oxygen in vitro. Dispersible microsensors were used to visualize the oxygen environment within in vitro tumor models, which allow for the informed generation of tumor models to more accurately capitulate the necessary oxygen environments.