Abstract
Specific molecular probes for reporting of CEs activity and pH are very rare in endoplasmic reticulum (ER). Herein, a pH-sensitive fluorescent probe for sensing endogenous CEs in ER was proposed and synthesized particularly. The methylfluorescein was selected as a new fluorogenic substrate exhibited excellent sensing properties, such as good membrane permeability, biocompatibility, photostability and low toxicity, considering the higher binding ability and elimination efficiency. In addition, with organelle targeting unit, the probe possessed ER-targeting ability and could be applied for the imaging of CEs level changes in cancer cells. Notably, all of these findings suggest that the probe holds potential advantages for further applications in biosystems in the future.