1. Author: Gene Yu Co-Authors: Dr. AlexBlake Dr. David Eddington July 29, 2010 NSF Research Experiences for Undergraduates (REU) in Novel Advanced Materials and Processing with Applications in Biomedical, Electrical and Chemical Engineering

2. Objective Design localized and automated delivery system for microfluidic brain slice devices (μBSDs) Delivers chemicals/drugs and gases Automatically mixes oxygen Characterize delivery of chemicals through tissue Image taken from Mohammed, J, Caicedo, H, Fall, C, & Eddington, D. (2008). Microfluidic add-on for standard electrophysiology chambers. Lab Chip, 8, 1048- 1055.

3. Motivation μBSDs allow in vitro study of: Neurogenesis Synaptogenesis Regeneration Protein expression Responses to physical trauma Image taken from http://www.koki.hu/cdnb/research/research.html Rambani, K, Vukasinovic, J, Glezer, A, & Potter, S. (2009). Culturing thick brain slices: an interstitial 3d microperfusion system for enhanced viability. Journal of Neuroscience Methods, 180, 243-254.

4. Relevance Chemical Delivery Spatial resolution Current systems affect entire slice with drug Desire stimulation of specific areas Oxygen Delivery Automatic Mixing Saves money Pre-mixing is not required Automation Multi-tasking Image modified from http://www.imagingeconomics.com/issues/articles/MI_2006-08_01.asp

5. Oxygen Mixing and Delivery Experimental Set-Up Y Connector Output Tube Valves Gas Feed Lines: 0% and 21% Oxygen concentration measured by a NeoFox Fiber Optic Oxygen (FOXY) sensor

6. Oxygen Mixing and Delivery Output

7. Oxygen Mixing and Delivery Graphical User Interface (GUI)

8. Delivery Characterization μBSD Design T Channel Delivery Channel Reservoir

9. Delivery Characterization Experimental Set-up μBSD Valve DI Water Lines T Channel Vacuum Line

10. Delivery Characterization No Tissue Delivery 10ms15ms20ms25ms 2x5ms3x5ms4x5ms5x5ms

11. Delivery Characterization Linear Relationships: No Tissue Width (µm) 860 1320

12. Delivery Characterization Linear Relationships: With Tissue Full Dose Chemical Delivery Pulsing Dose Chemical Delivery Maximum Intensities 02 4 6 Number of 5ms Pulses Intensity Time (min) 2 2 Maximum Intensities 010 20 30 Valve Open Time (ms) Intensity

13. Delivery Characterization GUI

14. Conclusions Oxygen Delivery Precise and accurate results Reliable oxygen switching Chemical Delivery Demonstrated linear relationship Area of effect: ~2mm x 2mm Selective and independent valve control

15. Acknowledgements Funding NSF-REU DoD-ASSURE EEC-NSF Grant # 0755115 REU Directors Christos G. Takoudis, Ph.D. Greg Jursich, Ph.D. Research Advisor David Thomas Eddington, Ph.D. Mentors Alexander Blake, Ph.D. Gerardo Mauleon