1. Alex Makowski Michael Hwang Jenny Lu Dr. John Wikswo
Three-dimensional microfabricated bioreactor and closed-loop control system
Alex Makowski Michael Hwang Jenny Lu
Dr. John Wikswo

2. Ultimate Project Goals
Computer modulated growth of tissue structures within microfluidic devices.
Possible uses include drug testing and dose determination, bypassing several stages of FDA trials.

3. Problem Statement- Design progress is blocked on three distinct fronts:
Sensors are required to provide computer with necessary information.
Bioreactor design limits the quantity and quality of cell morphology within the device.
Previously used cells (primary human fibroblasts) do not easily form tissue-like structures.

4. Subsequent Requirements:
Choose or design an appropriate sensor for pH measurements (most needed to determine cell metabolism and health).
Choose a cell line that will exhibit some kind of morphological change under successful conditions.
Redesign the bioreactor to incorporate new cell line and maximize efficiency of pH sensors.

5. Previous cell lines used…
Primary human fibroblast and endothelial cells
High cost
Lower passages
Difficult to exhibit 3D morphology
Need morphology as control

6. Why use MCF10A cell line? Human breast epithelial cell line (MCF10A)
Have in stock
Less expensive
Forms acinar morphology
Illustration courtesy of Weaver Lab

7. Cell Culture Model of Epithelial Acini
Confocal Imaging of Acini
from 3-D matrigel cultures
Illustration courtesy of Cassio Lynm, JAMA

8. Simplified Experimental Setup

9. Electrical connection for tubular Ti electrode
Copper wire
Copper plate
Titanium tube
Slide Courtesy of Sayed A. M. Marzouk
United Arab Emirates University

10. Electroplating the inner wall of Ti tube with IrO2
Tygon tube
To potentiostat
Titanium tube to be coated
(Working electrode)
Pt tube
(counter electrode)
Pt tube
(counter electrode)
pump
Electroplating solution
Slide Courtesy of Sayed A. M. Marzouk
United Arab Emirates University

11. Improvements over pH Optical fiber-type sensor
Improved response time (6 s vs. 2-3 min.)
Important for frequent measurements
Allows faster recalibration
No stagnant volume
T-junction for fiber creates a volume around sensor with little or no convective flow
Lack of convection  diffusion-limited analyte transport  even longer response time