biostudies-literatureLiu ZFoundation of National Facility for Translational MedicineFoundation of National Facility for Translational Medicine (Shanghai)Postdoctoral Research Foundation of ChinaNational Natural Science Foundation of ChinaShanghai Municipal Education Commission-Gaofeng Clinical Medicine Grant SupportShanghai Anticancer Association Eyas ProjectShanghai Sailing Program170https://www.ebi.ac.uk/biostudies/studies/S-EPMC8973627biostudies-literatureUnknown20(1)Contrast-enhanced MR angiography (MRA) is a critical technique for vascular imaging. Nevertheless, the efficacy of MRA is often limited by the low rate of relaxation, short blood-circulation time, and metal ion-released potential long-term toxicity of clinical available Gd-based contrast agents. In this work, we report a facile and efficient strategy to achieve Gd-chelated organic nanoparticles with high relaxivity for T₁-weighted MRA imaging. The Gd-chelated PEG-TCPP nanoparticles (GPT NPs) have been engineered composite structured consisting of Gd-chelated TCPP and PEG. The spherical structure of TCPP offers more chemical sites for Gd³⁺ coordination to improve the relaxivity and avoid leakage of the Gd³⁺ ions. The synthesized GPT NPs exhibit a high relaxation rate of 35.76 mM^- 1 s^- 1 at 3.0 T, which is higher than the rates for most reported MR contrast agents. Therefore, GPT NPs can be used for MRA with much stronger vascular signals, longer circulation time, and high-resolution arterial vascular visualization than those using clinical MR contrast agents at the same dose. This work may make the T₁ MRI contrast agents for high-resolution angiography possible and offer a new candidate for preclinical and clinical applications of MR vascular imaging and vascular disease diagnosis.Journal of nanobiotechnologyHigh relaxivity Gd³⁺-based organic nanoparticles for efficient magnetic resonance angiography.PMC8973627SACA-CY19A04TMSK-2021-12219YF141010021YF1411500821021902020M68132620191805Liu ZZhao MPeng WGu YFu ZNi DWang HGao HTang WfalseHigh relaxivity Gd³⁺-based organic nanoparticles for efficient magnetic resonance angiography.Contrast-enhanced MR angiography (MRA) is a critical technique for vascular imaging. Nevertheless, the efficacy of MRA is often limited by the low rate of relaxation, short blood-circulation time, and metal ion-released potential long-term toxicity of clinical available Gd-based contrast agents. In this work, we report a facile and efficient strategy to achieve Gd-chelated organic nanoparticles with high relaxivity for T₁-weighted MRA imaging. The Gd-chelated PEG-TCPP nanoparticles (GPT NPs) have been engineered composite structured consisting of Gd-chelated TCPP and PEG. The spherical structure of TCPP offers more chemical sites for Gd³⁺ coordination to improve the relaxivity and avoid leakage of the Gd³⁺ ions. The synthesized GPT NPs exhibit a high relaxation rate of 35.76 mM^- 1 s^- 1 at 3.0 T, which is higher than the rates for most reported MR contrast agents. Therefore, GPT NPs can be used for MRA with much stronger vascular signals, longer circulation time, and high-resolution arterial vascular visualization than those using clinical MR contrast agents at the same dose. This work may make the T₁ MRI contrast agents for high-resolution angiography possible and offer a new candidate for preclinical and clinical applications of MR vascular imaging and vascular disease diagnosis.2022-01-01T00:00:00Z2022 Mar2025-04-04T08:24:39.889Z2025-04-04T08:24:39.889ZS-EPMC89736273536121910.1186/s12951-022-01363-3