Additional file 1: Figure S1. of Enhanced MRI T 2 Relaxivity in Contrast-Probed Anchor-Free PEGylated Iron Oxide Nanoparticles

XRD patterns of bare Fe3O4 nanoparticles (SPION), PEGylated Fe3O4 nanoparticles (PEG-SPION) and pure PEG powder. Figure S2. (a-e) Bright field HRTEM images of PEG-SPION showing Fe3O4 cores fully coated with PEG. Figure S3. Zeta potential measurements showing the isoelectric point (IEP) of SPION and SPION stabilized with PEG (3350). Figure S4. DLS measurements of SPION and PEG-SPION dispersed in deionized water. Figure S5. A proposed mechanism of dipole cationic binding of ether group of PEG to Fe3O4 surface and hydration process of PEG for aqueous dispersibility. (DOCX 71194 kb)