Fabrication of a dual T1 and T2 contrast agent for magnetic resonance imaging using cellulose nanocrystals/Fe3O4 nanocomposite

Abstract A dual T 1 -T 2 contrast agent for magnetic resonance imaging was developed based on ultrasmall superparamagnetic Fe 3 O 4 nanoparticles. The magnetite nanoparticles were synthesized with thermal decomposition method, then loaded on hydrophilic cellulose nanocrystals-poly citric acid nanoplatform. The high saturation magnetization value (52.2 emu g −1 ), considerable relaxivity parameters r 1 (13.8 mM −1 s −1 ), r 2 (96.2 mM −1 s −1 ), and appropriate r 2 /r 1 (7.0) at 3.0 T demonstrated the significant enhancement effect of nanocomposite as a dual positive and negative contrast agent. In vitro cellular uptake study using inductively coupled plasma optical emission spectroscopy, in vitro cytotoxicity up to 200 μg mL −1 Fe with HeLa cell lines and colloidal stability investigations revealed that the sufficient cellular uptake, excellent biocompatibility and low toxicity of nanocomposite which is promising for its biomedical applications.