Title :
STW chemical sensors
Author :
Baer, R.L. ; Flory, C.A. ; Tom-Moy, M. ; Solomon, D.
Author_Institution :
Hewlett-Packard Lab., Palo Alto, CA, USA
Abstract :
A new kind of chemical sensor which is based on the surface transverse wave (STW) delay line is reported. This sensor is ideally suited to measurements of surface-attached mass under fluid immersion, and it is demonstrated operating under these conditions at 250 MHz. The mass sensitivity of an STW sensor is approximately 10 times greater than that of a thickness shear mode (TSM) or shear horizontal acoustic plate mode (SH-APM) sensor. The sensitivity is roughly comparable to that of a flexural plate wave (FPW) sensor, but it does suffer from the FPW sensor´s fragility. The STW device is applied to biosensing. By directly immobilizing antibodies on the surface, the sensor is used to detect human immunoglobulin G at a level of 33 nanomoles/liter
Keywords :
biosensors; chemical sensors; surface acoustic wave devices; ultrasonic delay lines; 250 MHz; STW sensor; biosensing; chemical sensors; fluid immersion; human immunoglobulin; mass sensitivity; surface transverse wave delay line; surface-attached mass; Acoustic devices; Acoustic measurements; Acoustic sensors; Biosensors; Chemical sensors; Delay lines; Rough surfaces; Surface acoustic waves; Surface roughness; Surface waves;
Conference_Titel :
Ultrasonics Symposium, 1992. Proceedings., IEEE 1992
Conference_Location :
Tucson, AZ
Print_ISBN :
0-7803-0562-0
DOI :
10.1109/ULTSYM.1992.275993
