Osteochondral Bioreactor Research Project

My sophomore year, I was given the opportunity to work with university professor Dr. Paolo Zunino researching microfluidic flow through bioreactors screening drugs used to treat drugs for osteoarthritis (OA). My job was to set up the ANSYS Fluid Flow (CFX) simulations to observe the amount of flow through the central chamber. Prior to working on this research, I had never had exposure to fluid mechanics or ANSYS simulations, so I sat in on Dr. Zunino's Intro to Fluid Mechanics class and spent my free time learning how to set up the simulations. By the end of the semester I was able to represent the model in ANSYS and learned how to interpret the data from the results of the simulation.

The following year, Dr. Zunino moved to Italy, and my research advisor became Riccardo Gottardi, Ph.D. I was instructed to work on a new bioreactor design in which optical access to the cells was granted compared to the previous model which contained no optical access. My role in the project was to alter the design of the fluid path in order to maximize drug exposure to the cells in the central chamber. An example of one of these fluid paths can be seen below.

The central chamber is filled with GelMA which has a relatively low permeability which leads to a low proportion of fluid flow through the central chamber and to the test cells. Because of this, the question that I addressed was how this design could be altered to enhance fluid flow to the cells and consequently increase the drug exposure. It was apparent that the following features could be changed to alter the fluid flow.

Multiple simulations to assess how each alteration affected the flow were performed which eventually lead to the development of relationships expressing how the velocity through the central chamber depends on each design dimension. After these relationships were found, the optimal design was found after considering the design constraints. The constraints necessary to consider were the resolution of the 3D printer, the minimum possible void size, the dimensions of a 96-well plate, and the overall design of the model to prevent features from intersecting. The finalized design is show below.

ANSYS testing predicted that this model would achieve nearly 10x the drug exposure through the central chamber compared to the simple ring model, and through experimental validation, this prediction was confirmed. This is because the step model increases the hydraulic resistance of the model. Because the resistance of the surrounding path increases, more fluid wants to move through the central chamber.

My research has been featured in two poster presentations, been published in Ingenium, an undergraduate research publication, and I am currently working towards having a manuscript published in Biotechnology and Bioengineering within the coming months. This research has taught me practical lessons such as scientific report writing, poster creation, and lab practices. More importantly, my work has helped me to discover my love for research and helped me to formulate my future path to graduate school.

Extra Documentation
Biomedical Microdevices Publication
Ingenium 2017 Publication
SSOE Summer Research Internship Two Page Abstract
Science 2016 Poster
Biomedical Engineering Society Annual Meeting Poster