Chitosan Oligosaccharide Lactate-Coated Ultrasmall Gadolinium Oxide Nanoparticles: Synthesis, In Vitro Cytotoxicity, and Relaxometric Properties.

In this study, hydrophilic and biocompatible chitosan oligosaccharide lactate (COL)-coated ultra-small gadolinium oxide nanoparticles (NPs) were synthesized through a one-pot polyol method and characterized by various experimental techniques. The cellular cytotoxicity assay indicated that the COL-coated gadolinium oxide NPs were non-toxic up to 500 M Gd. In addition, their water proton spin relaxivities (i.e., and ₂) were estimated to be 13.0 and 27.0 smM, respectively, which are higher than those of commercial magnetic resonance imaging (MRI) contrast agents. The application potential of the solution sample as a T MRI contrast agent was demonstrated by measuring map images in which dose-dependent contrast enhancements were observed.