A PDMS DIFFUSION PUMP FOR ON-CHIP FLUID HANDLING IN MICROFLUIDIC DEVICES

1. A PDMS DIFFUSION PUMP FOR ON-CHIP FLUID HANDLING IN MICROFLUIDIC DEVICES Mark A. Eddings and Bruce K. Gale Department of Bioengineering, University of Utah, Salt Lake City, UT Department of Mechanical Engineering, University of Utah, Salt Lake City, UT MicroTAS 2006, pp. 44-46 陳睿鈞

2. Outline • Introduction • Fabrication • Results and Discussion • Conclusion • References

3. Introduction • Fabrication • Results and Discussion • Conclusion • References

4. PDMS-Based Micropump Membrane pump generate flow Rapid off-chip valving Deflecting thin PDMS membranes Marc A. Unger, 2000 Power-free pump generate flow Gas permeability Additional preparation time one-time use applications K. Hosokawa, 2004

5. Diffusion-Based Membrane Pump Diffusion-based membrane pumping method Theoretical equation Applied pressure Flow rate p2 : feed pressure P1 : permeate pressure P : permeability coefficient A : diffusion area T : absolute temperature P atm : atmospheric pressure t : thickness of the membrane Applied vacuum

6. Introduction • Fabrication • Results and Discussion • Conclusion • References

7. Fabrication cast master mold 1.Lithography 2.Xurography(razor and writing) 65°C 45min SU-8 Silicon wafer vinyl PMMA wafer bonding Daniel A. 2005 65°C overnight D. Duffy, 1998

8. Microfluidic Device fluid channel layer diffusion membrane vacuum source layer Green : pressure/vacuum inlet Red : fluid wells Measuring flow rates Demonstrating dead-end chamber filling

9. Introduction • Fabrication • Results and Discussion • Conclusion • References

10. Flow Rate Characterization device equation : Variables : p2 : feed pressure A : diffusion area t : thickness of the membrane witha CCD camera

11. Comparing Theoretical Data With Experimental Data • Low aspect ratios and high aspect ratios. • Diffusion area was changed by membrane elongation and contact to the channel ceiling. low high FEA results for membrane deflection in microchannels ofaspect ratios 2 and 10

12. Fluid Handling • Fluid was easily manipulated through turns in cross intersections and filling dead-end channels and chambers. device 1 3 5 2 4 6 Three different fluids, red, green and blue, filling dead-end chambers.

13. Conclusion • The gas permeation pump provides a novel and convenient method for manipulating fluids within microfluidic devices. • Rapid dead-end channel filling and flow rates in the 200 nl·min-1 range have been demonstrated. • No need high frequency valve operation and significantly higher total chip areas. • Pumping and valving can be performed using one control line for pressure and one for the vacuum. one control line three control lines Marc A. Unger, 2000

14. References • Mark A Eddings and Bruce K Gale, “A PDMS-based gas permeation pump foron-chip fluid handling in microfluidicdevices”, J. Micromech. Microeng. 16 (2006) 2396–2402. • Marc A. Unger, Hou-Pu Chou, Todd Thorsen, Axel Scherer, Stephen R. Quake, “Monolithic Microfabricated Valves and Pumps by Multilayer Soft Lithography”, SCIENCE VOL 288 7 APRIL 2000, 113-116. • D. Duffy, J. McDonald, O. Schueller, G. Whitesides, “Rapid Prototyping of Microfluidic Systems in Polydimethylsiloxane”, Anal. Chem. 70, pp. 4974-4984. • K. Hosokawa, K. Sato, N. Ichikawa, M. Maeda, “Power-free PDMS microfluidic devices for gold nanoparticle-based DNA analysis”, Lab chip 2004, Vol. 4, pp.181–185. • Daniel A. Bartholomeusz, Ronald W. Boutté, and Joseph D. Andrade, “Xurography: Rapid Prototyping of Microstructures Using a Cutting Plotter”, 2005 J. Microelectromech. Syst. 141364–74.