Article

Electrical microfluidic pressure gauge for elastomer microelectromechanical systems.

Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA and Electrical Engineering Department, California Institute of Technology, Pasadena, California 91125, USA.
Journal of Applied Physics (impact factor: 2.17). 02/2007; 102(8):84909-849094. DOI:10.1063/1.2801008 pp.84909-849094
Source: PubMed

ABSTRACT We report on an electrical microfluidic pressure gauge. A polydimethylsiloxane microvalve closes at a characteristic applied pressure determined by the material's properties and the valve's dimensions. Hence, when the same pressure is applied to all valves of a heterogeneous valve array, some valves close while others remain open. The state of the array is combined with knowledge of the respective characteristic closing pressures of the individual valves to yield an estimate of the applied pressure. The state of each valve is obtained by electrical measurements, since the electrical resistance of the respective underlying fluid-filled channel increases by at least two orders of magnitude as the valve closes and its insulating elastomer material interrupts the electrical circuit. The overall system functions as a pressure gauge with electrical readout. This device would be a critical component in active pressure-regulation loops in future integrated microfluidic systems.

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    BioTechniques 01/2006; 40(1):85-90. · 2.67 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

active pressure-regulation loops
 
applied pressure
 
critical component
 
electrical circuit
 
electrical measurements
 
electrical microfluidic pressure gauge
 
electrical readout
 
electrical resistance
 
fluid-filled channel increases
 
heterogeneous valve array
 
individual valves
 
insulating elastomer material interrupts
 
material's properties
 
open
 
polydimethylsiloxane microvalve
 
pressure gauge
 
pressures
 
two orders
 
valve's dimensions
 
valves