A vacuum-isolated thermal microflowmeter for in-vivo drug delivery

Author

Li, Y. ; Baek, K. ; Gulari, M. ; Lin, D. ; Wise, K.D.

Author_Institution

Dept. of Electr. Eng. & Comput. Sci., Michigan Univ., Ann Arbor, MI

fYear

2005

fDate

Oct. 30 2005-Nov. 3 2005

Abstract

A thermal microflowmeter has been integrated into a bulk-micromachined recording probe to monitor drug delivery in the central nervous system at the cellular level. The flowmeter uses an arsenic-doped polysilicon heater/sensor supported on a dielectric membrane over the flow channel. It is capped by a vacuum-sealed microchamber to minimize heating of the surrounding tissue and maximize heating efficiency. Efficiencies of 18.8degC/mW in air and 17.4degC/mW in water are achieved. At an input power of 0.18mW, the flowmeter can detect a volumetric flow of 1.3nL/sec for a channel cross-section of 318mum₂, corresponding to a flow velocity of 4.2mm/sec

Keywords

biological tissues; cellular biophysics; drug delivery systems; flowmeters; microfluidics; microsensors; neurophysiology; probes; temperature sensors; 0.18 mW; 4.2 mm/s; arsenic-doped polysilicon heater/sensor; bulk-micromachined recording probe; cellular level; central nervous system; dielectric membrane; flow channel; in-vivo drug delivery; vacuum-isolated thermal microflowmeter; vacuum-sealed microchamber; Biosensors; Central nervous system; Chemicals; Dielectrics; Drug delivery; Heating; Mechanical sensors; Probes; Temperature sensors; Thermal sensors;

fLanguage

English

Publisher

ieee

Conference_Titel

Sensors, 2005 IEEE

Conference_Location

Irvine, CA

Print_ISBN

0-7803-9056-3

Type

conf

DOI

10.1109/ICSENS.2005.1597787

Filename

1597787