Originally Published EMDM
September 2003
Technology News
Thermistors Balance Size and Accuracy in Catheter Applications |
| MCD thermistors from BetaTherm have a minimum bead size of 0.38 mm OD. |
Temperature sensors have been developed to respond to market demands for miniaturization and accuracy. BetaTherm (Galway, Ireland), a provider of precision NTC thermistors, is offering a range of Micro Beta-Chip Probes, also called MCDs. The new sensors are suitable for a wide variety of catheter-administered procedures.
Current applications for these products include urology, ablation, and thermodilution. They are inserted in the body to measure or control temperature, assisting in the diagnosis and treatment of various medical conditions. Miniaturization is key in such biomedical applications. Temperature sensors sometimes have to fit in tubing as narrow as 0.5 mm. The MCD sensors come with a minimum bead size of 0.38 mm OD. Despite their small size, they are accurate to ± 0.5% at a single temperature point, and ±0.1% over a broader temperature range.
According to group marketing manager Kevin Moran, “What makes BetaTherm’s MCDs unique is the combination of small size and accuracy. We achieved small size through advances in the ceramic construction of the chip,” he adds. “At the same time, we developed a conductive polyimide Mylar electrical sleeve to insulate the chip.” This epoxy-filled tube balances environmental protection and thermal conductivity.
The company is also developing thermistors for existing and emerging catheter-administered applications in oncology and thermography. “Companies are now using thermistors to locate cancerous cells through differences in temperature,” says Moran. “Another emerging application is thermography, where thermistor sensitivity can help detect vulnerable plaques. We are working closely with several companies in these two areas.”
The MCD package comes with a specified time response of 200 milliseconds. This sensitivity makes the thermistors suitable for many gas- and liquid-sensing applications in the instrumentation sector.
Rita Emmanouilidou
Copyright ©2003 European Medical Device Manufacturer
