Metal-Assembled Collagen Peptide Microflorettes as Magnetic Resonance Imaging Agents.

Magnetic resonance imaging (MRI) is a medical imaging technique that provides detailed information on tissues and organs. However, the low sensitivity of the technique requires the use of contrast agents, usually ones that are based on the chelates of gadolinium ions. In an effort to improve MRI signal intensity, we developed two strategies whereby the ligand DOTA and Gd(III) ions are contained within Zn(II)-promoted collagen peptide () supramolecular assemblies.

Worm-Like Superparamagnetic Nanoparticle Clusters for Enhanced Adhesion and Magnetic Resonance Relaxivity.

Nanosized bioprobes that can highlight diseased tissue can be powerful diagnostic tools. However, a major unmet need is a tool with adequate adhesive properties and contrast-to-dose ratio. To this end, this study demonstrates that targeted superparamagnetic nanoprobes engineered to present a worm-like shape and hydrophilic packaging enhance both adhesion efficiency to target substrates and magnetic resonance (MR) sensitivity.

Hydrophilic packaging of iron oxide nanoclusters for highly sensitive imaging.

Superparamagnetic iron oxide nanoparticles (SPIONs) are used as imaging probes to provide contrast in magnetic resonance images. Successful use of SPIONs in targeted applications greatly depends on their ability to generate contrast, even at low levels of accumulation, in the tissue of interest. In the present study, we report that SPION nanoclusters packaged to a controlled size by a hyperbranched polyglycerol (HPG) can target tissue defects and have a high relaxivity of 719 mM(-1) s(-1), which was close to their theoretical maximal limit.

Controlling the morphology of metal-promoted higher ordered assemblies of collagen peptides with varied core lengths.

Self-assembling peptides have become an important subclass of next-generation biomaterials. In particular, materials that mimic the properties of collagen have received considerable attention due to the unique properties of natural collagen. Previous peptide-based designs have been successful in generating structures with morphological properties that were primarily determined by the type of self-assembling mechanism.

Selective decoration and release of His-tagged proteins from metal-assembled collagen peptide microflorettes.

Materials that mimic the extracellular matrix may serve as ideal delivery vehicles for biopolymers with biomedical applications. Herein we investigate dual His-tagged protein modification and release of metal-triggered, collagen peptide microflorettes by taking advantage of unsatisfied metal/ligands on or within the microflorette structures. Using GFP and RFP as model proteins for visualization, microflorettes were treated with His-tagged proteins either during or after particle assembly.