Characterization of a Bio ‐sourced, Fluorescent, Ratiometric pH Indicator with Alkaline pKa

We report the characterization of a pH ‐responsive fluorophore from an endophytic fungus isolated from sand pine. The endogenous fluorescence of the live organism was measured using fluorescence microscopy. Computational interpretation of the spectra was accomplished with time‐dependent density functional‐theory methods. The combin ed use of experimental and theoretically predicted spectra revealed the pH equilibria and photo‐excited tautomerization of the natural product, 5‐methylmellein. This product shows promise both as a stand‐alone pH‐indicating fluorophore, with alkaline pKa, and as "green" feedstock for synthesis of custom fluorophores.

Source: Photochemistry and Photobiology - June 18, 2020 Category: Science Authors: Samar Alheety, Domenic Valenti, Nirvani Mujumdar, Nakita Ellis, Andres D. Campiglia, James K. Harper, Emily C. Heider Tags: RESEARCH ARTICLE Source Type: research