A benzothiazole-based near-infrared fluorescent probe for selective turn-on detection of CORM-3

Tricarbonylchloro(glycinato)ruthenium(II) (CORM-3), a water-soluble carbon monoxide (CO)-releasing molecule, has demonstrated multifaceted therapeutic potential through its modulation of inflammatory responses, neuroprotection in traumatic brain injury, cardioprotection via intracellular pH regulation, and amelioration of metabolic and intestinal dysfunctions. However, the precise detection of CORM-3 in biological systems remains challenging, as existing fluorescent probes often require exogenous metal ions, lack specificity for CORM-3 over free CO, or suffer from suboptimal detection conditions. To address these limitations, we developed a benzothiazole-based near-infrared (NIR) fluorescence probe that enables a selective "turn-on" response to CORM-3. The probe exhibits high sensitivity (LOD = 0.034 μM) and a desirable quantitative correlation (0-266.6 μM), with robust resistance to CO interference. Buffer composition significantly affects detection performance, as phosphate-based buffers quench fluorescence, necessitating careful solvent selection. This probe successfully visualizes CORM-3 within living cells, providing a potential method for exploring its pharmacological mechanisms and therapeutic applications. These findings advance CORM-3 detection methodologies and support its clinical translation for managing CORMs-related pathophysiological processes.