A fluorescent probe for the Fe3+ ion pool in endoplasmic reticulum in liver cells

Abstract

We have presented rhodamine-derived Schiff base probes (1-6) selective of the Fe3+ ion in biological systems. In the presence of Fe3+ ions, the probes display new absorption and emission bands at 526 nm and 551 nm, respectively. Confocal microscopic analysis using the HepG2 cell line showed that probes 1-6 provide fluorescence Off-On changes caused by cellular Fe3+ ions, and demonstrated a largely enhanced fluorescence upon iron overloading of the cells. We also found that the Fe3+ ion-mediated fluorescence changes of probes 1-6 are mainly localized in the ER (Endoplasmic Reticulum) in HepG2 cells. Among them, probe 5 exhibits the highest selectivity for ER localization over the other organelles. (C) 2016 Elsevier Ltd. All rights reserved.