AUTHOR=Chen Yanqiu , Sun Xiaobo , Pan Wei , Yu Guifeng , Wang Jinping TITLE=Fe3+-Sensitive Carbon Dots for Detection of Fe3+ in Aqueous Solution and Intracellular Imaging of Fe3+ Inside Fungal Cells JOURNAL=Frontiers in Chemistry VOLUME=7 YEAR=2020 URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2019.00911 DOI=10.3389/fchem.2019.00911 ISSN=2296-2646 ABSTRACT=

In this article, the Fe3+-sensitive carbon dots were obtained by means of a microwave-assisted method using glutamic acid and ethylenediamine as reactants. The carbon dots exhibited selective response to Fe3+ ions in aqueous solution with a turn-off mode, and a good linear relationship was found between (F0-F)/F0 and the concentration of Fe3+ in the range of 8–80 μM. As a result, the as-synthesized carbon dots can be developed as a fluorescent chemosensor for Fe3+ in aqueous solution. Moreover, the carbon dots can be applied as a fluorescent agent for fungal bioimaging since the fungal cells stained by the carbon dots were brightly illuminated on a confocal microscopy excited at 405 nm. Furthermore, an increase in the concentration of intracellular Fe3+ could result in fluorescence quenching of the carbon dots in the fungal cells when incubated in the Tris-HCl buffer solution containing Fe3+. However, due to EDTA might hinder Fe(III) to enter the fungal cells, incubation in Fe(III)-EDTA complex solution exerted negligible effect on the fluorescence of fungal cells labeled by the carbon dots. Therefore, the carbon dots can serve as a potential probe for intracellular imaging of Fe3+ inside fungal cells.