limited contribution of standard MRI to the differentiation of benign and malignant tumors and to the characterization of tumor tissues. [2] Therefore, contrast agents are often required for clinical diagnosis in order to enhance signal differences. Approximately 40% of clinical MRI scans are performed with the assistance of contrast agents. [3] Gadolinium (Gd 3+ ) complexes such as Magnevist (Gd-DTPA) are one of the most commonly used T 1 contrast agents in clinics because of their thermodynamic stable and high paramagnetic. However, the lack of tissue specificity, rapid renal clearance, and limited relaxivity of Gd-DTPA mean higher doses during tumor imaging are required, [1b,4] which may cause potential harm to patients. [5] Loading small molecular contrast agent into nanocarriers can overcome their poor neoplastic targetability and modest signal-to-noise ratio, [6] but the short blood circulation of conventional nanocarriers limits further improvement in performance.The constant deformation of red blood cells (RBCs), one of the most common cells in blood, allows them to circulate for ≈120 days. [7] Healthy RBCs can deform and squeeze through
Magnetic resonance imaging (MRI) contrast agents, such asMagnevist (Gd-DTPA), are routinely used for detecting tumors at an early stage. However, the rapid clearance by the kidney of Gd-DTPA leads to short blood circulation time, which limits further improvement of the contrast between tumorous and normal tissue. Inspired by the deformability of red blood cells, which improves their blood circulation, this work fabricates a novel MRI contrast agent by incorporating Gd-DTPA into deformable mesoporous organosilica nanoparticles (D-MON). In vivo distribution shows that the novel contrast agent is able to depress rapid clearance by the liver and spleen, and the mean residence time is 20 h longer than Gd-DTPA. Tumor MRI studies demonstrated that the D-MON-based contrast agent is highly enriched in the tumor tissue and achieves prolonged high-contrast imaging. D-MON significantly improves the performance of clinical contrast agent Gd-DTPA, exhibiting good potential in clinical applications.