Share Email Print
cover

Proceedings Paper

Defect tolerance in microfluidic chambers for capacitive biosensors
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Biomedical sensors combining microfluidic and electronics capabilities require defect avoidance in both the electronic processing circuits and microfluidic areas. Microfluidic sensors involve sealed channels through which sample fluids containing biomedical materials flow. Inserting microchannels between capacitive plates enable the detection of biomaterials by the changes in capacitance. However, faults occur when foreign particles, or fluid bubbles get lodged in the paths blocking a channel, thereby affecting the measured C. To achieve fault tolerance we investigate a Cathedral Chamber design, with pillars supporting the roof at regular intervals. This prevents single blockages from stopping fluid flow through the system in a channel, as there are many paths. We discuss the potential causes and effects of such blockages. Monte Carlo simulations show that the Cathedral Chamber design significantly increases lifetime of the system, an average of 6 times more particles are required before full blockage occurs compared to an array of parallel channels. Fluid flow modeling shows parallel channels show rapid rise of pressure with the number of blockages while the Cathedral chamber shows much slower rise, which reaches a plateau pressure until it is blocked. The impact of defects on the capacitive measurement is also discussed. Finally, an interesting application, one that uses patches of single chain Fragment variables (scFv's), the active part of antibodies, is also discussed.

Paper Details

Date Published: 17 February 2010
PDF: 11 pages
Proc. SPIE 7593, Microfluidics, BioMEMS, and Medical Microsystems VIII, 75930V (17 February 2010); doi: 10.1117/12.845388
Show Author Affiliations
Glenn Chapman, Simon Fraser Univ. (Canada)
Bonnie L. Gray, Simon Fraser Univ. (Canada)
Vijay K. Jain, Univ. of South Florida (United States)


Published in SPIE Proceedings Vol. 7593:
Microfluidics, BioMEMS, and Medical Microsystems VIII
Holger Becker; Wanjun Wang, Editor(s)

© SPIE. Terms of Use
Back to Top