Application of catheter-tip i.s.f.e.t. for continuousin vivo measurement
- 98 Downloads
A catheter-tip pH sensor was developed for possible clinical and biomedical application, using an ion-sensitive field-effect transistor (i.s.f.e.t.). Its signal drift in buffer solutions during continuous measurement was less than 3 mV in 24 h (equivalent to about 0·05 pH in 24 h). The electric insulation was perfect when soaked in buffer solutions for more than 3 months. A continuousin vivo pH measurement was successfully achieved in nonheparinised arterial blood of a japanese monkey. There was no significant sign of clot formation for 8 hours. It revealed quick responses to respiratory acidosis and alkalosis, and the observed pH values were in accordance with those confirmed by a blood pH analyser. Also, a catheter-tip pCO2 sensor was prepared, using the catheter-tip pH i.s.f.e.t. The response time was 2 min for a 90% change in CO2 tension. The muscle pCO2 monitoring tested with it indicated a similar result to those with medical mass spectrometer.
KeywordsBlood monitoring Catheter-tip pH sensor I.S.F.E.T. Miniature pH sensor Miniature pCO2 sensor
Unable to display preview. Download preview PDF.
- Esashi, M. andMatsuo, T. (1978)IEEE Trans.,BME-25, 184.Google Scholar
- Severinghaus, J. W. andBradley, A. F. (1958)J. Appl. Physiol.,13, 515.Google Scholar
- Fung, D. J., Cheung, P. W., Wong, S. H., Topich, J. A. andKo, W. H. (1975)Abstract No. 81, The Electrochemical Society, ACS 153rd Meeting, Seattle, Washington, May 21–26.Google Scholar
- Nakashima, T. andTakakura, K. (1975)Japanese Patent (Kokai) 50-2086.Google Scholar