A non-invasive osteopontin-targeted phase changeable fluorescent nanoprobe for molecular imaging of myocardial fibrosis.

Due to the elevated fatality rate of cardiovascular diseases, myocardial fibrosis emerges as a prominent pathological alteration in the majority of heart ailments and their associated pathologies, thereby augmenting the likelihood of sudden cardiac death. Consequently, the prompt and obligatory identification of myocardial fibrosis assumes paramount importance in averting malignant incidents among patients afflicted with cardiac disorders. Herein, with higher expression osteopontin (OPN) found in cardiac fibrosis tissue, we have developed a dual-modality imaging probe, namely OPN targeted nanoparticles (OPN@PFP-DiR NPs), which loaded perfluoropentane (PFP) for ultrasound (US) and 1,1-dioctadecyl-3,3,3,3-tetramethylindotricarbocyanine iodide (DiR) for near-infrared fluorescence (NIR) of molecular imaging, to investigate the molecular features of cardiac fibrosis using US and NIR imaging. Subsequently, the OPN@PFP-DiR NPs were administered intravenously to a mouse model of myocardial infarction (MI). The US and NIR molecular imaging techniques were employed to visualize the accumulation of the nanoparticles in the fibrotic myocardium. Hence, this research presents a valuable noninvasive, cost-effective, and real-time imaging method for evaluating cardiac fibrosis, with promising clinical applications.