Document Type

Dissertation

Date of Award

8-31-2022

Degree Name

Doctor of Philosophy in Chemical Engineering - (Ph.D.)

Department

Chemical and Materials Engineering

First Advisor

Roman S. Voronov

Second Advisor

Piero M. Armenante

Third Advisor

Edward L. Dreyzin

Fourth Advisor

Treena Livingston Arinzeh

Fifth Advisor

S. Basuray

Sixth Advisor

Gal Haspel

Abstract

Cell experiments are ubiquitous to the studies of biology, tissue engineering, and drug testing. However, complex cultures are notoriously difficult to analyze nondestructively. Instead, they are typically evaluated using sacrificial means: such as histology sectioning, or by crushing the sample for chemical plate-reader assays. This is inefficient, costly, and results in data discontinuity because each new experiment only provides a single time point. Likewise, delivering new cells or chemicals to custom locations without disturbing an on-going experiment is also difficult. This limits the type of experiments that are feasible. And the inability to deliver nutrients results in cell death in the deep portions of the thick cultures. Therefore, there is a need to be able to perform fluid and cell manipulations (i.e., delivering, probing, removing, and sampling) within the complex living cultures, continuously and with minimal effects to the studied biology.

The broad goal of this dissertation is to resolve all these bottlenecks simultaneously, and additionally create a breadth of new experimental possibilities, by interlacing cell cultures with microscopic (i.e., “microfluidic”) channels and ports. Specifically, localized minimally disruptive manipulation (i.e., delivery/probing) of cells/fluids within the cultures can be achieved by distributing individually-actuatable (termed as “addressable”) ports at targeted locations (or “addresses”). These manipulations can be executed and monitored via automation, to enable unprecedented experiment precision and to reduce human labor costs. Lastly, if such a technology were to be developed, it should be straightforward/inexpensive for others to make; and it should be commercialized to accelerate mass adoption.

To that end, Chapter 1 of this dissertation overviews the significance of the envisioned technology and highlights the difficulties with generating it. It then presents a do-it-yourself custom ultraviolet (UV) mask aligner that is developed to help cheaply fabricate such technology in house; and demonstrates the equipment’s capabilities. Chapter 2 discusses a use-case of creating various microfluidic mazes and forks using the proposed custom UV mask aligner, which is then used to study directional-decision making during the migration of fibroblast cells in micro-confinement. Chapter 3, then, lays out the blueprints of the addressable microfluidic plumbing and demonstrates a two-dimensional proof of concept device that performs both additive and subtractive localized cell and fluid manipulations. Next, Chapters 4 and 5 touch upon the versatility of the technology, by discussing its two potential applications: namely, making the microfluidic device implantable for in vivo studies and biodegradable for tissue engineering, respectively. Additionally, Chapter 5 also discusses the various materials properties that are necessary to scale up the technology three-dimensional (3D) microfluidic scaffolds fabricated using automated methods, such as 3D printing techniques. And Chapter 6 reviews state of the art in 3D printing equipment, with the aim of choosing the best machine for fabricating the proposed addressable microfluidic devices. Lastly, Chapter 7 presents a significant on-going commercialization effort, to make the addressable microfluidic cell culturing technology more accessible to the consumer market.

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.