Chiral Iron Oxide Supraparticles Enable Enantiomer-dependent Tumor-Targeted Magnetic Resonance Imaging.

The chemical, physical and biological effects of chiral nanomaterials have inspired general interest and demonstrated the important advantages in fundamental science. Here, we fabricated chiral iron oxide supraparticles (Fe 3 O 4 SPs) modified by chiral penicillamine (Pen) molecules with a g-factor of approximately 2 × 10 -3 at 415 nm, these SPs acted as a high-quality magnetic resonance imaging (MRI) contrast agent. Therein, the transverse relaxation efficiency and T 2 -MRI results demonstrated the chiral Fe 3 O 4 SPs had a r 2 relaxivity of 157.39 ± 2.34 mM -1 ·S -1 for D-Fe 3 O 4 SPs and 136.21 ± 1.26 mM -1 ·S -1 for L-Fe 3 O 4 SPs due to the enhanced electronic transition dipole moment for D-Fe 3 O 4 SPs compared with L-Fe 3 O 4 SPs. The in vivo MRI results showed that D-Fe 3 O 4 SPs exhibited a two-fold lower contrast ratio than L-Fe 3 O 4 SPs, which enhanced targeted enrichment in tumor tissue, such as prostate cancer, melanoma, and brain glioma tumor. Notably, it w as found that D-Fe 3 O 4 SPs had a 7.7-fold higher affinity for the tumor cell surface receptor cluster-of-differentiation 47 (CD47) than L-Fe 3 O 4 SPs. These findings uncovered that chiral Fe 3 O 4 SPs act as a highly effective MRI contrast agent for targeting and imaging broad tumors, thus accelerating the practical application of chiral nanomaterials and deepening the understanding of chirality in the biological and non-biological environments. This article is protected by copyright. All rights reserved.