Dye molecules are important in bioanalytical chemistry and are used for protein detection, which can support the detection and identification of diseases. Alexa Fluor® Carboxylic Acid dyes in particular are used for cellular labeling and detection. UV/visible absorption and emission spectra have been obtained for a series of Alexa Fluor® Carboxylic Acid dyes. Studies of the effects of solvent polarity and pH on the spectra are being performed. Experiments with Alexa Fluor® 488 Carboxylic Acid dye involving a series of alcohol solvents of varying chain lengths (methanol, ethanol, propanol, and butanol) have been completed. The use of only alcohol solvents allows for the polarity to be changed without changing the functional group. The fluorescence intensity decreases with increasing chain length of the alcohol. In the absorption spectra, a slight increase in the wavelength of maximum absorption (λ<sub>max</sub>) was observed as polarity decreases. These effects are examined in terms of the energetics of frontier orbitals. Experiments to investigate the effects of pH on the various spectra are currently underway.

Fluorescence studies on a series of carboxylic acid dyes

251st National Meeting (2016)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.