Hydrogel-based microsensors for wireless chemical monitoring.
Biomed Microdevices
; 11(3): 529-38, 2009 Jun.
Article
en En
| MEDLINE
| ID: mdl-18335316
ABSTRACT
We report fabrication and characterization of a new hydrogel-based microsensor for wireless chemical monitoring. The basic device structure is a high-sensitivity capacitive pressure sensor coupled to a stimuli-sensitive hydrogel that is confined between a stiff porous membrane and a thin glass diaphragm. As small molecules pass through the porous membrane, the hydrogel swells and deflects the diaphragm which is also the movable plate of the variable capacitor in an LC resonator. The resulting change in resonant frequency can be remotely detected by the phase-dip technique. Prior to hydrogel loading, the sensitivity of the pressure sensor to applied air pressure was measured to be 222 kHz/kPa over the range of 41.9-51.1 MHz. With a pH-sensitive hydrogel, the sensor displayed a sensitivity of 1.16 MHz/pH for pH 3.0-6.5, and a response time of 45 minutes.
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Técnicas Biosensibles
Tipo de estudio:
Diagnostic_studies
Idioma:
En
Revista:
Biomed Microdevices
Asunto de la revista:
ENGENHARIA BIOMEDICA
Año:
2009
Tipo del documento:
Article
País de afiliación:
Estados Unidos