| 研究課題/領域番号 |
22K20520
|
|---|
| 研究機関 | 国立研究開発法人国立循環器病研究センター |
|---|
研究代表者 |
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)
|
|---|
| 研究期間 (年度) |
2022-08-31 – 2024-03-31
|
| キーワード | Fluorescein / 4 arm PEG / Fe3O4 / Supramolecular assembly |
|---|
| 研究実績の概要 |
Iron oxide nanoparticles (IONPs) are promising contrast agents in terms of their high T1/T2 relaxation time and biocompatibility. However, IONPs easily accumulate in the liver and possess shorter circulation time. Therefore, microvessel imaging is not possible with them. Nanoparticles size between ~100 to 200 nm should be optimal to achieve maximum stability and longer circulation time. Firstly, we have synthesized fluorescein/Fe3O4 conjugated PEG that can form supramolecular self-assemble structure by the fluorescein groups stacked with one another. We have performed different characterization test as FTIR, UV-spectra and XPS to confirm the synthesis. Dynamic light scattering (DLS) analysis has been performed to confirm the change in hydrodynamic radius. Further we have evaluated self-assemble structure stability with different time, pH and temperature. Fluorescein conjugation enhance stability of self-assembly structure at normal pH, and the structure get disintegrated in alkaline pH. Moreover, blood circulation test and organ accumulation analysis have performed on small animal. These results were presented at 44th annual meeting of Japanese Society of Biomaterials (JSB), and 72nd annual meeting of Society of Polymer Science Japan (SPSJ).
|
| 現在までの達成度 (区分) |
現在までの達成度 (区分)
2: おおむね順調に進展している
理由
The research is progress well and on the time. We have successfully synthesized fluorescein/Fe3O4 conjugated PEG that can form supramolecular self-assemble structure. Moreover, we have observed disintegration behavior of supramolecular structure at alkaline ph. This phenomenon is very important for urinary track excretion during in-vivo experiments. We are analyzing in-vivo behavior of supramolecular self-assemble structure.
|
| 今後の研究の推進方策 |
For the next stage, we will synthesis fluorescein/Fe3O4 conjugated PEG with different structure and molecular weight as liner, 4-arm and 8-arm with 10kDa, and 20kDa. We will inject them in rat to analyze blood circulation, organ accumulation and urinary track excretion. H&E staining and Prussian blue staining will be performed to examine impact and accumulation of the contrast agent in different organs. Finally, we will perform rat cerebrovascular imaging using 7T MRI. Based on the findings in the first year, the applicant is going to write and publish a paper in an international journal. Also, the applicant expects to present the new findings this year at an international conference.
|
| 次年度使用額が生じた理由 |
we have to perform in-vivo experiments on rats. Therefore, we have to synthesize material in large quantity and need to buy many rats for experiment. optimization of material to get higher resolution of cerebrovascular imaging is required to perform experiment several times. so, it is required to incurring amount to be used next fiscal year.
|
