We describe the preparation of superparamagnetic nanoclusters (SNCs) by fine-tuning of the seed Fe3O4 nanoparticle sizes to enhance and their T2 relaxivity can be increased by > 4-fold. Therefore, with 11 nm seed core and PVA coating, SNC-11 exhibit a higher T2 relaxivity than other cluster condition. So fabricating the cluster, seed size is the most important influence the T2 relaxivity. As well as, in vitro cellular imaging results demonstrated the strong potential of SNCs for clinical applications by targeting affinity. According to the experiments, with 11 nm seed core and PVA coating, SNC-11 exhibited the highest T2 relaxivity of 454 mM-1s-1 due to the strong seed size effect on their magnetic sensitivity, indicating superior magnetic resonance (MR) contrast efficiency. Further in vitro cellular imaging results demonstrated the strong potential of SNCs for clinical applications.

1. Introduction
 2. Materials and Methods
  2.1. Materials
  2.2. Synthesis of iron oxide magnetic nanoparticles
  2.3. Fabrication and sorting of clusters
  2.4. Synthesis of CMPVA
  2.5. Antibody conjugation of SNC
  2.6. Characterization
 3. Result and Discussion
 5. Conclusions
 참고문헌

• Youngjun Ro(Department of Chemical and Biomolecular Engineering, Yonsei University) | 노영준
• Joseph Park(Department of Chemical and Biomolecular Engineering, Yonsei University) | 박요셉
• Byunghoon Kang(Department of Chemical and Biomolecular Engineering, Yonsei University) | 강병훈
• Jaemin Lee(Department of Chemical and Biomolecular Engineering, Yonsei University) | 이재민
• Young-Min Huh(Department of Radiology, College of Medicine, Yonsei University) | 허용민
• Seungjoo Haam(Department of Chemical and Biomolecular Engineering, Yonsei University) | 함승주