Transcript Presentation 5

Instrumented NanoPhysiometer for
High Throughput Drug Screening
D. Michael Ackermann, Jon Payne,
Hilary Samples, James Wells
Labview Front Panel
IMAGE
Big Picture
Applications:
A Research Tool
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Target Population:
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Protoype of research tool
Private research of BioMEMS group of VUSE BME
dept
Market Demand:
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Custom project for specific research
Future implications to broad market
High throughput screening
Pharmaceutical Testing
Toxicology
Motivation
Limited study of cell life, activity, and volumes
Previous methods:
Single phase, stationary state
Microliter scale & volumes
Nanophysiometer
Nanoliter Scale
Real Time Monitoring
Decrease: Reagents (if
Processing
Time
any!)
128 Well Plate Assays
Project Goals
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Develop nanoliter sized cell culture volume
On-chip pumps for low flow perfusion and drug
administration.
Thin film microelectrodes for monitoring of
various analytes such as pH, oxygen, glucose
and lactose in the media.
Optimize cell culture conditions to maintain cell
viability over long periods of time.
Develop a Labview based user interface for
mircofluidic control of the NanoPhysiometer
The NanoPhysiometer
Goals:
Develop On-Chip Drug
Delivery Systems
To Achieve Desirable Low
Flow Profiles
Using Peristaltic Pumping
Providing Ideal Parameters
for Cell Viability
800 um
Physiometer Mask Design
Electrodes
800 um
Microfluidics
Pneumatics
Physiometer Design Concerns
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Filter Size
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3 um, 5 um, 8 um
Channel Aspect Ratio
Space between fluidic
and pneumatic layers
Peristaltic Pumps/Valves
Fluidics
Layer
STATUS:
Working! Currently
just optimizing.
Flexible PDMS Membrane
(Valve)
[1] S.R. Quake and A. Scherer, "From Micro to Nano Fabrication with Soft Materials", Science 290: 1536-40 (2000).
[2] M.A. Unger, H.-P. Chou, T. Thorsen, A. Scherer, and S.R. Quake, "Monolithic Microfabricated Valves and Pumps by Multilayer Soft Lithography", Science 288: 113116 (2000).
Electrochemical Monitoring
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Use integrated thin film microelectrodes to
monitor physiological parameters
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pH, glucose, etc.
Electrodes coated with a substrate specific
oxidase
Catalyze reaction producing H2O2
 H2O2 then detected
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STATUS: Will be integrated once fluidics/pneumatics
are performing optimally: hard to make!
Optimize Cell Culture Conditions
Determine minimal flow rates
for maintaining vitality &
sufficient perfusion
 Allow for physiological
measurements
 Low flow for detectable pH and
electrochemical differential
STATUS: We seeded and imaged
fibroblast in devices of various
sized filters for observation,
testing of cell attachment , and
minimal survival.
FIBROBLASTS
*3-8 mm when spherical,
(flat, dendrite-like when attached)
*1-2 day doubling time
*Robust
*Medium- antibiotics,
vitamins, essential AA
Atmospheric Cell Culture Conditions
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Cells demand optimal temperature and CO2/O2 levels
PDMS is gas permeable
Plexiglas enclosure
 Contained, humidified
incubator environment of 5%
CO2
Heated Microscope
stage
 Maintains optimal heated
http://www.cyto.purdue.edu/flowcyt/educate/photos/confocal/images.htm
environment of 37 C
LabView programming
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User control of nanophysiometer system
Program Presets based on experimental needs
 Manual Control of Pumps and valves
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Measurements & Data acquisition
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Show parameter measurements
Time-Lapse Image Capture
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Qualitative analysis
STATUS: Nearly complete.
Labview Front Panel
IMAGE
Schematic
Camera
LabView
Nanophysiometer
Electrode
D/A Converter
Pneumatic
Controller
JAN
Literature & Patent
Search
Define Goals & Project
Approach
Design Mask
Prototype/Device
Fabrication
Programming
Cell Culture
Operation
Assessment &
Evaluation
Final Paper &
Presentation
FEB
MAR
APR
Budget
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Mask of device design- $600/mask
PDMS kit - $15
Cell culture supplies- $300/month
Tubing, wiring, etc.- ~$10
Electrodes- $500 (owned by lab)
References
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Unger, Quake, et. al. Monolithic Microfabricated Valves and
Pumps by Multilayer Soft Lithography. Science. Vol. 288. April
7, 2000
Ho, Chih-Ming. Fluidics – The Link Between Micro and Nano
Sciences and Technologies. 0-7803-5998-4/01. 2001 IEEE
Arik, Zurn, et. al. Design, Fabrication and ExperimentalNumerical Study of PZT Sensors. MSM 2000. Puerto Rico.
Gonzalez, Moussa. Simulation of MEMS Piezoelectric
Micropump for Biomedical Applications. 2002. Algor
Incorporated; Technical Document.
Bar-Cohen, Chang. Piezoelectrically Actuated Miniature
Peristaltic Pump. March 2000. Proceeding of 2000 SPIE Smart
Structures and Materials Symposium. No. 3992-103
Acknowledgements
 Dr.
Franz Baudenbacher
 David Schaffer
 Andreas
 Nanodelivery, Inc.