A systematic study of core size and coating thickness on manganese-doped nanocrystals for high T2 relaxivity as magnetic resonance contrast agent

Abstract

We describe a systematic study of coating thickness and their effect on different core sizes for the optimized preparation of highly sensitive manganese-doped magnetic nanocrystals (MnMNCs) to be served as magnetic resonance (MR) contrast agent. From these efforts, MnMNCs with 12 nm core and DA-PEG2k coating demonstrated that T2 relaxivity (r2) was increased by 7.29-fold (r2 value: 452 mM−1 s−1) compare to conventional iron oxide (CLIO) and remarkable colloidal stability in various physiological conditions. Further in vitro cellular MR imaging results showed that MnMNC-PEGs were biocompatible and well suited for medical applications. This study will provide a useful synthetic strategy for the development of highly effective MR contrast agents.