Abstract by Nathan Giauque
Chemistry and Biochemistry
Low-volume Detection in Spectroscopy
From the Beer-Lambert law we learn that longer path lengths are required to detected more dilute concentrations of an analyte. Increasing the path length through a sample is often difficult, especially if limited amounts of the analyte are present. Our group is investigating an alternative to physically extending path length by using a silica-packed column. We hypothesize that the light scattering through the silica particles will increase the optical path length and yield greater signal. Experimentally, we have focused on fluorescence and absorbance spectroscopy. Fluorescence was tested by exciting solutions of rhodamine B with a 530 nm laser. We are also investigating applications to fluorimeter cells by using low-volume, silica-packed columns held within a standard cuvette-sized holder, for use in most fluorimeters. Absorbance is currently being tested using similar methods to our fluorescence experiments using cobalt nitrate as our analyte. Results from our work thus far are promising and applications are being pursued further.