Albumin-templated manganese carbonate nanoparticles for precise magnetic resonance imaging of acute myocardial infarction

Myocardial infarction (MI) is a major cause of death worldwide. Early and precise diagnosis of myocardial viability after MI is extremely important for effective treatment and prognosis evaluation. Herein, we developed the BSA-templated manganese carbonate (MnCO ₃ @BSA) nanoparticles as an MR imaging contrast agent for accurate detection of the infarcted regions. The chemophysical features, targeting capability toward the infarct, and biocompatibility were evaluated. The nanoparticles showed superior chemical stability. In vitro study suggested that the MnCO ₃ @BSA nanoparticles do not enter normal cardiomyocytes. MR imaging indicated that the MnCO ₃ @BSA with a high longitudinal ( r ₁ ) relaxivity of 5.84 mM ⁻¹ s ⁻¹ at physiological condition specifically accumulated into the infarcted regions of myocardial ischemia/reperfusion (I/R) mice. In addition, the MnCO ₃ @BSA nanoparticles exhibited low cytotoxicity to cardiomyocytes, no damage to organs and good hemocompatibility. Thereby, the MnCO ₃ @BSA nanoparticles manifested great potential as an extracellular contrast agent of MR imaging for sensitive and specific detection of the infarcted regions during acute myocardial I/R injury.