Visualising superfine cerebrovasculature in MRI using supramolecular self-assembly

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K20520
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0403:Biomedical engineering and related fields
• Research Institution: National Cardiovascular Center Research Institute
• Principal Investigator: SONI RAGHAV 国立研究開発法人国立循環器病研究センター, 研究所, リサーチフェロー (10967863)
• Project Period (FY): 2022-08-31 – 2024-03-31
• Keywords: Nanoparticles / Fluorescein / PEG / Self-assembly / MRI contrast

Outline of Final Research Achievements

In this study, we created a self-assembled iron oxide nanoparticle-based contrast agent for high-resolution imaging of the cerebrovasculature. The branched polyethylene glycols having approximately 10 kDa of molecular weight are conjugated with iron oxide nanoparticles and fluorescein. The self-assembled fiber structure is concentration-dependent and formed by electrostatic interaction. Self-assembly fibers measuring 120 nm in length and 50 nm in width are detected at 25 mg/ml. Furthermore, self-assembly contrast administered intravenously in a rat model revealed a more significant cerebral microvascular network than conventional MRI imaging. The research result was presented at several domestic conferences and published in an international journal.

Free Research Field

Biomaterials and Imaging

Academic Significance and Societal Importance of the Research Achievements

This study demonstrated that self-assemble contrast, when delivered into the circulation, can visualize microvascular networks that conventional MRI imaging cannot, making it an effective new imaging tool for diagnosing cerebral atherosclerosis and stroke.