Instrumented Nano Physiometer for High Throughput Drug Screening

Instrumented Nano. Physiometer for High Throughput Drug Screening D. Michael Ackermann, Jon Payne, Hilary Samples, James Wells

Overall Project Definition Develop a miniaturized microfluidic-based cell culture apparatus for high throughput parallel drug screening with on-chip monitoring of cell physiology. Develop On-Board Drug Delivery Systems To Achieve Desirable Low Flow Profiles Using Peristaltic Pumping Providing Ideal Parameters for Cell Viability

Big Picture Applications: A Research Tool n Target Population: n n n Protoype of research tool Private research of Bio. MEMS group of VUSE BME dept Market Demand: n n Custom project for specific research Future implications to broad market High throughput screening Pharmaceutical Testing Toxicology

Motivation 128 well plate assay technique Limitations: stationary state cell study microliter reagent volumes n microliter scale studies n Nanophysiometer Nanoliter Scale Real Time Monitoring Decrease: Reagents (if any!) Processing

Project Goals n n n Develop and Fabricate nanoliter sized cell culture volumes with flow through perfusion Design on-chip peristaltic pumps for low volume perfusion and drug administration. Design and incorporate thin film microelectrodes in the inflow and outflow structures for differential electrochemical monitoring of various analytes such as p. H, 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 Nano. Physiometer

Nanoliter-sized Cell Culture n ** Nanophysiometer ** Accurate small-scale study of cell function n Flow Through Perfusion Continuous Media turn-over n Cell Filters 300 um STATUS: Mask came in on Friday after 2 week delay! 500 um

Soft Lithography STATUS: Made practice channels and will make master on Tuesday

Peristaltic Pumps Fluidics Layer STATUS: Have pneumatic controller and pneumatic mask are currently programming the Labview interface 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 n Use integrated thin film microelectrodes to monitor physiological parameters n n p. H, glucose, etc. Electrodes coated with a substrate specific oxidase Catalyze reaction producing H 2 O 2 n H 2 O 2 then detected n STATUS: Will be integrated once cell lines are self sustaining and fluidics/pneumatics are performing

Physiometer Mask Design Electrodes Microfluidics Pneumatics

Lab. View programming n User control of nanophysiometer system Program Presets based on experimental needs n Manual Control of Pumps and valves n n Measurements & Data acquisition n n Show parameter measurements Time-Lapse Image Capture n Qualitative analysis STATUS: Developing pneumatic controller interface code

Labview Control Panel IMAGE

Schematic Camera Lab. View Nanophysiometer Electrode D/A Converter Pneumatic Controller

Optimize Cell Culture Conditions n n Determine minimal flow rates for maintaining vitality Allow for physiological measurements Exp: p. H differential as an indicator of metabolic rate STATUS: This week we are starting our own cell culture line of Fibroblasts from starter cells from Evgeni in Chem. E Department. n

Atmospheric Cell Culture Conditions Maintain Temperature and CO 2/O 2 levels n PDMS gas permeable n Plexiglas enclosure n Heated Microscope stage n http: //www. cyto. purdue. edu/flowcyt/educate/photos/confocal/images. htm

Timeline JAN Literature & Patent Search Define Goals & Project Approach Design Mask Prototype/Device Fabrication Programming Operation Assessment & Evaluation Final Paper & Presentation FEB MAR APR

Budget Mask of device design- $600/mask n PDMS kit - $15 n Cell culture supplies- $300/month n Tubing, wiring, etc. - ~$10 n Electrodes- $500 (owned by lab) n

References n n n 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 Experimental. Numerical 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 n Dr. Franz Baudenbacher n David Schaffer n Nanodelivery, Inc.