Two techniques are described for the measurement of fluid temperatures in microfluidic systems based on temperature-dependent fluorescence. In the first technique, a single, strongly temperature-dependent fluorophore, rhodamine B, is used as the basis for fluorescence intensity-based thermometry. For the second technique, two different fluorophores are used with different emission wavelengths, and the ratio of the signals at the two different colors is used to calculate the temperature. Both techniques are easy to implement with a standard fluorescence microscope and CCD camera. In addition, the methods can be used to measure fluid temperatures with micrometer spatial resolution and millisecond time resolution. The methods are demonstrated by measuring temperature distributions within a variety of microfluidic devices resulting from either direct contact heating or Joule heating as fluid is electrokinetically pumped through the systems.
Proceedings Title: AIP Conference Proceedings: Temperature: ITS MEASUREMENT AND CONTROL IN SCIENCE AND INDUSTRY
Conference Dates: October 21-24, 2002
Conference Location: Chicago, IL
Conference Title: 8th International Temperature Symposium
Pub Type: Conferences