An ESIPT-boosted NIR nanoprobe for ratiometric sensing of carbon monoxide via activatable aggregation-induced dual-color fluorescence

Abstract

Carbon monoxide (CO) is a crucial gaseous signaling molecule that regulates various physiological and pathological processes, and may exert an anti-inflammatory and protective role in drug-induced liver injury (DILI). Despite this, understanding the exact relationship between CO and the occurrence and development of DILI remains challenging. Hence, there is an urgent need to develop a reliable and robust tool for the rapid visual detection and assessment of CO in this context. Herein, we presented a novel near-infrared (NIR) fluorescent nanoprobe with aggregation-induced emission (AIE) properties and excited-state intramolecular proton transfer (ESIPT) characteristics for the detection and imaging of CO both in vitro and in vivo. Simultaneously, the nanoprobe enables self-assembly form nanoaggregates in aqueous media with high biocompatible, which can sense CO in situ through the conversion of yellow-to-red fluorescence facilitated aggregation-induced dual-color fluorescence. What is more, this nanoprobe shows ratiometric respond to CO, which demonstrates excellent stability, high sensitivity (with a detection limit of 12.5 nmol/L), and superior selectivity. Crucially, this nanoprobe enables the visual detection of exogenous and endogenous CO in living cells and tissues affected by DILI, offering a user-friendly tool for real-time visualization of CO in living system. Hence, it holds great promise in advancing our understanding of CO's role.