Fe 3+ and H + ‐triggered “Turn‐on” Fluorescence Probe Based on Lysosomal‐targeted RBH‐EdC for Monitoring Intragastric Acidity
Year: 2025
Type: article
Abstract: The long‐term visualization of intracellular Fe 3+ dynamics and lysosomal activity is crucial for investigating the physiological roles and functions of lysosomes during the growth of organisms. The lysosome‐targeted fluorescent probe (RBH‐EdC), derived from rhodamine‐nucleoside conjugates, demonstrates a sophisticated dual‐activation design: one is Fe 3 ⁺ response, triggering spirolactam ring‐opening to form xanthine structures, resulting in ≥ 1000‐fold fluorescence enhancement with visible colorimetric transition (colorless→pink). Another is pH sensitivity, demonstrating protonation‐dependent fluorescence amplification at the dC at site N3 (pK a = 2.9), achieving a 30‐fold intensity increase at pH 2.5 within the 1.0–5.0 range. Remarkably, the RBH‐EdC/Fe 3 ⁺ complex showed a further significant 20‐fold fluorescence enhancement at pH 3.0. This Fe 3 ⁺/H⁺ co‐activated “turn‐on” system provides exceptional signal amplification for both in vitro and in vivo applications, enabling precise exploration of lysosome‐related biological processes, including the response of the pH microenvironment, real‐time monitoring of lysosomal pH dynamics, in situ measurement of gastric acidity levels, and potential application in gastric ulcer diagnostics.
Source: Chemistry - A European Journal
Authors: Weiqing Xu, Linyu Zeng, Jiarong Nan, Weiran Ling, Hai Xiong
Institution: Shenzhen University
Language: English
Subfield: Spectroscopy
Field: Chemistry
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W4414081150