In Vivo Monitoring of Hydrogen Polysulfide via a NIR-Excitable Reversible Fluorescent Probe Based on Upconversion Luminescence Resonance Energy Transfer

Abstract

Hydrogen polysulfide (H 2 S n ), derived from hydrogen sulfide (H 2 S), has attracted increasing attention, which is suggested to be the actual signal molecule instead of H 2 S in physiological and pathological processes. Reversible detection of H 2 S n through a NIR-excitable fluorescence probe is an effective means to understand its functions but is quite challenging. Herein, we reported a NIRexcitable ratiometric nanoprobe for the reversible detection of H 2 S n based on luminescence resonance energy transfer principle with upconversion nanoparticles as the energy donor and an organic molecule, SiR1, as the energy acceptor and reversible recognition unit of H 2 S n . The as-prepared nanoprobe exhibited high selectivity and fast response for the reversible detection of H 2 S n , which can monitor the formation and consumption of endogenous H 2 S n in living cells. Because of the reduced autofluorescence by NIR excitation, it was successfully applied for tracking the fluctuation of H 2 S n concentration of mice in physiological and pathological processes including inflammation and liver injury.

Optical and Photoacoustic Imaging In Vivo: Opportunities and Challenges

“…Then, the quenched fluorescence was activated by H 2 S n due to the nucleophilic attack to the Si-xanthene ring, accompanied by the decreased absorption. The proposed responsive nanoprobes provided a powerful tool for H 2 S n detection in vivo and contributed to the investigation of precise molecular imaging …”

A chemiluminescent sensor for imaging endogenous hydrogen polysulfides in a living system

“…18 Even though the reported NIR fluorescent probes show better penetration, they usually require shorter excitation wavelengths, which are difficult to penetrate deep tissues. [19][20][21] Moreover, the usage of exogenous excitation light sources brings inevitable photobleaching, background interference, and spontaneous luminescence, thus restricting the analytical performance of probes in the cases of sensing and imaging. [22][23][24][25][26][27][28] Subsequently, bioluminescent probes have been developed based on the firefly luciferase-luciferin system to solve the problems of dependence on exogenous excitation light sources.…”

A Fluorometer-Free Experimental Course for Fluorescence Analysis Based on Smartphone and Image/Data-Processing Software Using a Synthetic Sensor

“…Quantitative sensing technologies play an essential role in scientific research and modern chemical analysis. − Among these technologies, fluorescence analysis is characterized by high sensitivity and great simplicity, making it widely used for the quantification of heavy metal ions, warfare agents, biomolecules, etc. − Their fluorescence intensity increases or decreases after reaction with the target analyte, thus allowing us to obtain the concentration of target analyte by calculating the variation of fluorescence intensity. Several courses have been developed to enhance students’ understanding of fluorescence analysis and have shown significant results. , However, a fluorometer is generally required to measure the value of fluorescence intensity, which poses certain challenges in undergraduate teaching.…”