Chiral Iron Oxide Supraparticles Enable Enantiomer‐Dependent Tumor‐Targeted Magnetic Resonance Imaging

Abstract The chemical, physical and biological effects of chiral nanomaterials have inspired general interest and demonstrated important advantages in fundamental science. Here, chiral iron oxide supraparticles (Fe₃O₄ SPs) modified by chiral penicillamine (Pen) molecules with g‐factor of ≈2 × 10⁻³ at 415 nm are fabricated, and these SPs act as high‐quality magnetic resonance imaging (MRI) contrast agents. Therein, the transverse relaxation efficiency and T₂‐MRI results demonstrated chiral Fe₃O₄ SPs have a r₂ relaxivity of 157.39 ± 2.34 mM⁻¹·S⁻¹ for D‐Fe₃O₄ SPs and 136.21 ± 1.26 mM⁻¹·S⁻¹ for L‐Fe₃O₄ SPs due to enhanced electronic transition dipole moment for D‐Fe₃O₄ SPs compared with L‐Fe₃O₄ SPs. The in vivo MRI results show that D‐Fe₃O₄ SPs exhibit two‐fold lower contrast ratio than L‐Fe₃O₄ SPs, which enhances targeted enrichment in tumor tissue, such as prostate cancer, melanoma and brain glioma tumors. Notably, it is found that D‐Fe₃O₄ SPs have 7.7‐fold higher affinity for the tumor cell surface receptor cluster‐of‐differentiation 47 (CD47) than L‐Fe₃O₄ SPs. These findings uncover that chiral Fe₃O₄ 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 biological and non‐biological environments.