A mitochondria-targeted NIR fluorescence/photoacoustic dual-modality probe for highly sensitive and selective imaging of HClO in vivo.

Hypochlorous acid (HClO) represents a typical endogenous reactive oxygen species primarily generated within mitochondria, with excessive levels intimately linked to numerous pathological conditions. Consequently, the detection of mitochondrial HClO in vivo holds significant importance in the biomedical realm. Near-infrared fluorescence (NIRF)/photoacoustic (PA) dual-modality imaging techniques offer enhanced accuracy in biological imaging. Herein, a novel mitochondria-targeted NIRF/PA dual-modality probe (MB-ClO) has been designed and synthesized. MB-ClO exhibits remarkable selectivity, ultra-sensitivity (LOD = 5.1 nM) towards HClO, coupled with a swift fluorescence response (<10 s). MB-ClO possesses low toxicity and excellent water solubility, making it suitable for biological applications. Moreover, MB-ClO is capable of targeting mitochondria. MB-ClO has been successfully utilized to detect HClO in biological systems. In addition, MB-ClO has been utilized for NIRF/PA dual-modality imaging in a mouse model of rheumatoid arthritis, demonstrating its extensive application potential and value in biomedical research.