Pneumatically driven peristaltic micropumps utilizing serpentine-shape channels

This study presents a novel pneumatic micropump featuring a serpentine-shape (S-shape) microchannel. Fluid is driven through the device by the hydrodynamic pressure generated by the peristaltic action of membranes located at the intersections of the fluidic microchannel and the S-shape microchannel. The pneumatic micropump is fabricated in PDMS (polydimethylsiloxane) using MEMS (micro-electro-mechanical-systems)-based techniques. The micropump provides an improved pumping rate and is controlled using a single electromagnetic valve (EMV) switch. The experimental results reveal that the pumping rate can be increased by increasing the operational frequency of the EMV, the pressure of the externally supplied compressed air or the number of membranes. As the compressed air travels along the S-shape microchannel, it causes the membranes to deflect. The time-phased deflection of successive membranes along the microchannel length generates a peristaltic effect which drives the fluid along the microfluidic channel. The maximum attainable pumping rate is influenced by the time interval between the deflections of adjacent membranes, and is therefore affected by the geometric characteristics of the serpentine microchannel. The back pressure of the serpentine-shape micropump is measured at a fixed peak frequency to prove its ability to overcome the fluidic resistance. The optimum operating conditions and geometric parameters of the micropump are verified experimentally. It is found that the maximum pumping rate is 7.43 µl min−1 and is provided by a micropump with seven membranes actuated by 20 psi air pressure and 9 Hz operational frequency.

[1]  B. W. van Oudheusden The determination of the effective ambient temperature for thermal flow sensors in a non-isothermal environment , 1999 .

[2]  G. Stemme,et al.  Consecutive Microcontact Printing — Ligands for Asymmetric Catalysis in Silicon Channels , 2001 .

[3]  D. J. Harrison,et al.  Microchip systems for immunoassay: an integrated immunoreactor with electrophoretic separation for serum theophylline determination. , 1998, Clinical chemistry.

[4]  Joe T. Lin,et al.  Microfabricated Centrifugal Microfluidic Systems: Characterization and Multiple Enzymatic Assays , 1999 .

[5]  Ming Lei,et al.  Hard and soft micromachining for BioMEMS: review of techniques and examples of applications in microfluidics and drug delivery. , 2004, Advanced drug delivery reviews.

[6]  Paul J. Mcwhorter,et al.  Materials issues in microelectromechanical devices: science, engineering, manufacturability and reliability , 2003 .

[7]  Shigeru Nakagawa,et al.  Micropump and sample-injector for integrated chemical analyzing systems , 1990 .

[8]  A. Manz,et al.  Integrated electroosmotic pumps and flow manifolds for total chemical analysis systems , 1991, TRANSDUCERS '91: 1991 International Conference on Solid-State Sensors and Actuators. Digest of Technical Papers.

[9]  Paul C. H. Li,et al.  Transport, manipulation, and reaction of biological cells on-chip using electrokinetic effects. , 1997, Analytical chemistry.

[10]  O. Jeong,et al.  Fabrication and test of a thermopneumatic micropump with a corrugated p+ diaphragm , 2000 .

[11]  R S Foote,et al.  Microchip device for cell lysis, multiplex PCR amplification, and electrophoretic sizing. , 1998, Analytical chemistry.

[12]  Takehiko Kitamori,et al.  Microchip-based chemical and biochemical analysis systems. , 2003, Advanced drug delivery reviews.

[13]  Takehiko Kitamori,et al.  Microchannel-assisted thermal-lens spectrometry for microchip analysis. , 2003, Journal of chromatography. A.

[14]  J. Fluitman,et al.  A thermopneumatic micropump based on micro-engineering techniques , 1990 .

[15]  William C. Tang,et al.  Laterally Driven Polysilicon Resonant Microstructures , 1989 .

[16]  Weiyuan Wang,et al.  Future of microelectromechanical systems (MEMS) , 1996 .

[17]  Juan G. Santiago,et al.  A review of micropumps , 2004 .

[18]  E. S. Kim,et al.  Micropump based on PZT unimorph and one-way parylene valves , 2004 .

[19]  Gwo-Bin Lee,et al.  Automatic bio-sampling chips integrated with micro-pumps and micro-valves for disease detection. , 2005, Biosensors & bioelectronics.

[20]  P. Barth,et al.  Silicon micromechanical devices , 1983 .

[21]  Baisheng Wu,et al.  A continuum model for size-dependent deformation of elastic films of nano-scale thickness , 2004 .

[22]  A. Manz,et al.  Micro total analysis systems. 1. Introduction, theory, and technology. , 2002, Analytical chemistry.

[23]  J. G. Smits Piezoelectric micropump with three valves working peristaltically , 1990 .

[24]  Roberto Raiteri,et al.  Micromechanics senses biomolecules , 2002 .

[25]  A. Manz,et al.  Micro total analysis systems. 2. Analytical standard operations and applications. , 2002, Analytical chemistry.

[26]  M. Richter,et al.  A bidirectional silicon micropump , 1995 .

[27]  K K Jain Biotechnological applications of lab-chips and microarrays. , 2000, Trends in biotechnology.

[28]  Carles Cané,et al.  Multi-range silicon micromachined flow sensor , 2004 .

[29]  S. Quake,et al.  Monolithic microfabricated valves and pumps by multilayer soft lithography. , 2000, Science.

[30]  O. Jeong,et al.  A phase-change type micropump with aluminum flap valves , 2003 .