Dual-State Emissive Mitochondrial Viscosity Probe for Long-Term Imaging of Rheumatoid Arthritis

Abstract

Rheumatoid arthritis (RA) is a destructive autoimmune disease that seriously affects human health. Due to the lack of a cure for RA, a good prognosis largely depends on early diagnosis and effective treatment monitoring of RA. Therefore, the development of fluorescent probes capable of real-time detection of RA is of great significance. Dual-state emission (DSE) molecules can emit light in both dilute solution and solid state, making them ideal fluorophores for constructing fluorescent probes. However, there are currently no reports of DSE molecule-based fluorescent probes for RA imaging. Herein, we report a fluorescent probe <b>MQP-Boc</b> based on a novel DSE molecule for effective RA imaging. <b>MQP-Boc</b> selectively responds to viscosity with sensitive fluorescence changes at 667 nm and is mitochondria targetable. Cell imaging studies show that <b>MQP-Boc</b> can detect changes in mitochondrial viscosity and perform long-term imaging of mitochondria, which is significantly superior to that of the control probe <b>MQP-Ac</b>. Imaging studies on a mouse model of RA induced by λ-carrageenan show that <b>MQP-Boc</b> has excellent real-time and long-term imaging capabilities for RA. Besides, with <b>MQP-Boc</b>, significant increases in joint tissue viscosity were found during the RA process. All results indicate that <b>MQP-Boc</b> is an effective new tool for studying and diagnosing RA.