The average size of our synthesized USPIO was 4.7 nm, and the UVHP potential was −27.7 mV with good dispersion, and our results confirm that UVHP targeted not only the cells with high VCAM-1 expression but also the RA mice joint sites, which indicates the potential of UVHP as a T1 contrast agent. Here, VCAM1 is linked to rheumatoid arthritis.