These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Observing the Reversible Single Molecule Electrochemistry of Alexa Fluor 647 Dyes by Total Internal Reflection Fluorescence Microscopy. Author: Fan S, Webb JEA, Yang Y, Nieves DJ, Gonçales VR, Tran J, Hilzenrat G, Kahram M, Tilley RD, Gaus K, Gooding JJ. Journal: Angew Chem Int Ed Engl; 2019 Oct 07; 58(41):14495-14498. PubMed ID: 31418504. Abstract: Alexa Fluor 647 is a widely used fluorescent probe for cell bioimaging and super-resolution microscopy. Herein, the reversible fluorescence switching of Alexa Fluor 647 conjugated to bovine serum albumin (BSA) and adsorbed onto indium tin oxide (ITO) electrodes under electrochemical potential control at the level of single protein molecules is reported. The modulation of the fluorescence as a function of potential was observed using total internal reflectance fluorescence (TIRF) microscopy. The fluorescence intensity of the Alexa Fluor 647 decreased, or reached background levels, at reducing potentials but returned to normal levels at oxidizing potentials. These electrochemically induced changes in fluorescence were sensitive to pH despite that BSA-Alexa Fluor 647 fluorescence without applied potential is insensitive to pH between values of 4-10. The observed pH dependence indicated the involvement of electron and proton transfer in the fluorescence switching mechanism.[Abstract] [Full Text] [Related] [New Search]