A Substituted‐Rhodamine‐Based Reversible Fluorescent Probe for In Vivo Quantification of Glutathione

Abstract

Quantifying glutathione (GSH) in cells and organisms is of great significance for understanding the mechanism of oxidative stress in various physiological and pathological processes. However, the quantification by fluorescence bioimaging in living tissues has much stricter requirements than the "Petri dish"-cultured cells in flat plates. Based on the evaluation of the electronic structure and steric hindrance-tuned reactivity of phospha-substituted rhodamine with GSH, a reversible Förster resonance energy transfer (FRET) probe ZpSiP with a distinct performance (K d = 4.9 mM, t 1/2 = 0.57 s, k = 81 M À 1 s À 1 ) is developed for real time quantifying GSH in living cells. Furthermore, the near-infrared (NIR) probe succeeded in sensitively tracking the dynamics of GSH in the real organisms bearing tumors, chronic renal failure, and liver fibrosis for unveiling the related pathological processes. We believe that the advance in chemistry with quantitative analysis methods will initiate more promising progress and broad applications.

Recent Progress in the Rational Design of Biothiol-Responsive Fluorescent Probes

“…The Cui group developed a novel reversible NIR ratiometric fluorescent probe 38 ( EpSiP ) by molecular engineering, enabling in vivo quantification of GSH in intact tissues and animals ( Scheme 14 ) [ 85 ]. Probe 38 was constructed on a FRET scaffold, where Si-rhodamine and phospha-rhodamine were used as the FRET acceptor and donor, respectively.…”