We describe a new approach to fluorescence sensing based on fluorescence polarization measurements. The sensing device consists of an analyte sensitive fluorescence probe and a reference fluorophore which is not affected by the analyte. Combined emission from probe and reference passes through two adjacent orthogonally oriented polarizers and is viewed with second analyzer polarizer. Changes in the probe intensity result in changes in the polarization of the combined emission. The analyzer polarizer is rotated to yield equal intensity from both sides of two orthogonally oriented polarizers. So constructed sensor earlier was used for manual visual detection of RhB in intralipid and to measure pH using 6-carboxyfluorescein. A sensor equipped with the simple electronic detection system of a dual photocell and a Watson bridge improves the accuracy. We used this device with UV hand lamp, electroluminescent light source or LED to detect pH, oxygen and calcium. This sensing method is generic and can be used with any fluorophore which displays an analyte-dependent change in intensity.
|Number of pages||7|
|Journal||Proceedings of SPIE - The International Society for Optical Engineering|
|State||Published - 1 Dec 1999|
|Event||Proceedings of the 1999 Chemical Microsensors and Applications II - Boston, MA, USA|
Duration: 19 Sep 1999 → 20 Sep 1999