Main-chain modified polysiloxane towards ratiometric fluorescent probes for dynamic visualization of ClO-/GSH oxidation reduction fluctuations in vivo

Redox homeostasis contributing to the maintenance of normal cellular physiological states. On the contrary, off-kilter redox as a resolution member in the production of cardiovascular disease, rheumatoid arthritis, and even cancer. To date, a few reports have focused on ratiometric sustainable assays for ClO - and GSH cycling due to the headache of transient reactivity, ultra-low concentrations and short lifetimes. However, methods for the design of ratiometric fluorescent probes also need to be further expanded. In this paper, we present a novel approach to the construction of ratiometric fluorescent probes via controlled modification of polysiloxane backbones. We aimed at the controlled assembly of a biocompatible, more pliable and stable “Si-O-Si” bridging framework, “red gene” perylenetetracarboxylic anhydride and “green gene” molecular sensors, successfully constructing a dual-excitation, dual-emission ratiometric fluorescent probe ( PBN-1 ) with favorable biosafety properties, excellent photostability and promising sensitivity. PBN-1 sustainability dynamically tracked ClO - /GSH oxidation fluctuations in HepG2 cells and zebrafish. Notably, PBN-1 distinguished dramatically the fluctuations of ClO - /GSH in zebrafish at different growth and developmental periods. We expect that PBN-1 could provide an effective method for the design of future ratiometric fluorescent probes and expand the application of polysiloxanes in bioimaging. • A novel strategy for constructing ratiometric fluorescent probes. • Dual-excitation, dual-emission polymer ratiometric fluorescent probes. • PBN-1 demonstrated superior sensitivity to ClO - [LOD = 3 σ /k (~ 2.3 nM)]. • PBN-1 revealed fluctuating levels of ClO - /GSH in cells and zebrafish via ratiometric channels.