Event Title

PH Dependent Spectral Analysis of Fluorescein for Application in Environmental Studies

Mentor 1

David Garman

Mentor 2

Marcia Silva

Location

Union Wisconsin Room

Start Date

29-4-2016 1:30 PM

End Date

29-4-2016 3:30 PM

Description

Fluorescein is a chemical dye that has been widely used as a model compound to perform environmental studies. Some of these applications include groundwater tracing for measuring aquifer properties, determination of flow paths in channels, and adsorption experiments to evaluate the ability of adsorbents to remove organic pollutants from the water column. Although sodium fluorescein is a very attractive dye for laboratory studies, it offers several challenges such as high sensitivity to light, tendency to break down over time, large fluorescence yield, and requires safety precautions when handing in powered form. The goal of this research is to perform experiments to understand the changes in absorbance or fluorescence spectra in relation to pH and concentration. There is some previous work reported on fluorescein on buffer solutions, however no data under environmental conditions. A spectral analysis will be performed at varying fluorescein concentrations and pH using a Synergy 4 plate reader. Sufficiently low fluorescein concentrations must be used to yield absorbance and fluorescence measurements within range of the plate reader. Examination of the point at which absorbance and florescence do not change due to fluctuations in pH will be determined by graphical analysis techniques. This optimal wavelength known as the isosbestic point will be determined by performing absorbance and fluorescence scans over the wavelength ranges of 350 to 550 nm and 400 to 700 nm respectively, and will test fluorescein samples at pH values from 4 to 10. Suggested wavelength ranges have been chosen due to the assumption that fluorescence and absorbance will show mid-range peak values, however wavelength ranges may be refined throughout experimentation if results show otherwise. Conclusions will present the results for the isosbestic criteria for sodium fluorescein in relation to varying pH and concentration.

This document is currently not available here.

Share

COinS
 
Apr 29th, 1:30 PM Apr 29th, 3:30 PM

PH Dependent Spectral Analysis of Fluorescein for Application in Environmental Studies

Union Wisconsin Room

Fluorescein is a chemical dye that has been widely used as a model compound to perform environmental studies. Some of these applications include groundwater tracing for measuring aquifer properties, determination of flow paths in channels, and adsorption experiments to evaluate the ability of adsorbents to remove organic pollutants from the water column. Although sodium fluorescein is a very attractive dye for laboratory studies, it offers several challenges such as high sensitivity to light, tendency to break down over time, large fluorescence yield, and requires safety precautions when handing in powered form. The goal of this research is to perform experiments to understand the changes in absorbance or fluorescence spectra in relation to pH and concentration. There is some previous work reported on fluorescein on buffer solutions, however no data under environmental conditions. A spectral analysis will be performed at varying fluorescein concentrations and pH using a Synergy 4 plate reader. Sufficiently low fluorescein concentrations must be used to yield absorbance and fluorescence measurements within range of the plate reader. Examination of the point at which absorbance and florescence do not change due to fluctuations in pH will be determined by graphical analysis techniques. This optimal wavelength known as the isosbestic point will be determined by performing absorbance and fluorescence scans over the wavelength ranges of 350 to 550 nm and 400 to 700 nm respectively, and will test fluorescein samples at pH values from 4 to 10. Suggested wavelength ranges have been chosen due to the assumption that fluorescence and absorbance will show mid-range peak values, however wavelength ranges may be refined throughout experimentation if results show otherwise. Conclusions will present the results for the isosbestic criteria for sodium fluorescein in relation to varying pH and concentration.