We have proposed recently that the DO3A-N-α-(amino)propionate chelator and its amide conjugates are leads to targeted, high relaxivity, safe contrast agents for magnetic resonance imaging. In this work we illustrate further the expeditious nature and robustness of the synthetic methodologies developed by preparing the DO3A-N-(α-pyrenebutanamido)propionate chelator. Its Gd(3+) chelate retains th...

Maghemite particles are used as T₂ contrast agents for magnetic resonance imaging, especially for molecular and cellular imaging. Linear clusters of particles - called nanoworms - were recently developed to enhance the targeting efficiency. In this work, the magnetic and NMR relaxation properties of these nanoworms are studied at multiple magnetic fields. After the usual saturation at 0.5 T, th...

Magnetic Resonance Imaging instruments rely on a contrast agent to provide high-resolution images of tissues in vivo. However, current clinical contrast agents are hindered by low relaxivity and fast correlation time, necessitating high injection dosages. These concerns, among others, have driven the development of a class of protein-based contrast agents (ProCAs), by design of lanthanide bindi...

In recent years, there has been increasing interest in developing a multifunctional nanoscale platform for cancer monitoring and chemotherapy. However, there is still a big challenge for current clinic contrast agents to improve their poor tumor selectivity and response. Herein, we report a new kind of Gd complex and folate-coated redox-sensitive lipid-polymer hybrid nanoparticle (Gd-FLPNP) for...

The development of upconversion nanoparticles (UCNs) for theranostics application is a new strategy toward the accurate diagnosis and efficient treatment of cancer. Here, magnetic and fluorescent lanthanide-doped gadolinium oxide (Gd2O3) UCNs with bright upconversion luminescence (UCL) and high longitudinal relaxivity (r1) are used for simultaneous magnetic resonance imaging (MRI)/UCL dual-moda...

As bimodal magnetic-fluorescent imaging agents, the preparation of ZnS:Tb,Gd and ZnS:Er,Yb,Gd nanoparticles via a facile homogeneous precipitation method is reported. The results show that these nanoparticles are almost spherical in shape with a diameter of 100-200 nm approximately and a major phase of wurtzite-structured ZnS. The products can successfully label the human hepatocellular carcino...

Here we report a supramolecular hydrogel based on Gd(III)-peptide complexes with dramatically enhanced magnetic resonance (MR) performance. The hydrogelations were formed by adding Gd(III) ion to the nanofiber dispersion of self-assembling peptides naphthalene-Gly-Phe-Phe-Tyr-Gly-Arg-Gly-Asp (Nap-GFFYGRGD) or naphthalene-Gly-Phe-Phe-Tyr-Gly-Arg-Gly-Glu (Nap-GFFYGRGE). We further showed that, by...

Introduction Single injection moving table peripheral contrast enhanced MR angiography is increasingly utilized for the evaluation of peripheral atherosclerotic occlusive disease (PAOD). Peripheral MRA (pMRA) is typically performed using a moving table technique during first passage of double to triple dose (0.2-0.3 mmol/kg) extracellular gadolinium chelate. The objective of this study was to c...

We introduce a mechanism for ion sensing by MRI in which analytes compete with paramagnetic ions for binding to polydentate chelating agents. Displacement of the paramagnetic ions results in alteration of solvent interaction parameters and consequent changes in relaxivity and MRI contrast. The MRI changes can be tuned by the choice of chelator. As an example, we show that calcium-dependent disp...