Revealing the redox status in endoplasmic reticulum by a selenium fluorescence probe.

As an important organelle, the endoplasmic reticulum (ER) participates in the synthesis and secretion of various proteins, glycogen, lipids and cholesterol in eukaryotic cells. In this work, an endoplasmic reticulum-targeted reversible fluorescent probe (ER-Se) was designed and synthesized. The probe, based on a selenide group, shows high sensitivity and good selectivity toward HClO (LOD = 0.85 μM). In addition, the probe has reversible capability towards HClO/GSH. Most importantly, co-location experiment results indicated that the probe exhibited a great ability to target the endoplasmic reticulum. Furthermore, the probe was successfully applied to detect exogenous and endogenous HClO in ER and monitored the redox status changes during ER stress.