Detection of pH variation using modified microcantilever sensors

Citation
Hf. Ji et al., Detection of pH variation using modified microcantilever sensors, SENS ACTU-B, 72(3), 2001, pp. 233-238
Citations number
21
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Spectroscopy /Instrumentation/Analytical Sciences","Instrumentation & Measurement
Journal title
SENSORS AND ACTUATORS B-CHEMICAL
ISSN journal
0925-4005 → ACNP
Volume
72
Issue
3
Year of publication
2001
Pages
233 - 238
Database
ISI
SICI code
0925-4005(20010210)72:3<233:DOPVUM>2.0.ZU;2-N
Abstract
A micromechanical technique for measuring solution pH using modified silico n (SiO2) and silicon nitride (Si3N4) microcantilevers is described. As the modified surface of the cantilever accumulates charge proportional to the p H of the surrounding liquid, the cantilever undergoes bending due to the di fferential surface stress. Results are presented for chemically modified (4 -aminobutyltriethoxysilane, 11-mercaptoundecanoic acid) and metal-modified (Au/Al) surfaces over a pH range 2-12. Aminosilane-modified SiO2/Au cantile vers performed robustly over pH range 2-8 (49 nm deflection/pH unit), while Si3N4/Au cantilevers performed well st pH 2-6 and 8-12 (30 nm deflection/p H unit). The influences of other ions on cantilever bending were found to b e negligible below 10(-2) M concentration. (C) 2001 Elsevier Science B.V. A ll rights reserved.