This research is to develop a method for measurement of the refractive index (RI) of very small volume liquid samples. This measurement is achieved by launching light into one end of an optical fiber with a necked region that is interacting with the sample, and measuring of the amount of light lost from the fiber at the other end. The loss of light at the fiber waist provides a direct measure of the RI of the sample. Placing the fiber waist within a coaxial flow cell enables RI measurements in volumes of thirty nanoliters or smaller, making measurement suitable for use in either liquid chromatography (LC) or capillary electrophoresis (CE). Additional refinement of the process, such as the development of fabrication procedures, and identifying and minimizing noise sources will also be accomplished. This technology will allow the use of RI measurements as a routine detection method in very low sample volumes in LC and CE. These unique characteristics make the detector employable in the various markets for RI detectors.
