Magneto-acoustic protein nanostructures for non-invasive imaging of tissue mechanics in vivo.

Measuring cellular and tissue mechanics inside intact living organisms is essential for interrogating the roles of force in physiological and disease processes. Current agents for studying the mechanobiology of intact, living organisms are limited by poor light penetration and material stability. Magnetomotive ultrasound is an emerging modality for real-time in vivo imaging of tissue mechanics.

Hyperthermia Effect of Nanoclusters Governed by Interparticle Crystalline Structures.

Magnetic nanoparticles have an important role as heat generators in magnetic fluid hyperthermia, a type of next-generation cancer treatment. Despite various trials to improve the heat generation capability of magnetic nanoparticles, iron oxide nanoparticles are the only approved heat generators for clinical applications, which require a large injection dose due to their low hyperthermia efficiency. In this study, iron oxide nanoclusters (NCs) with a highly enhanced hyperthermia effect and adjustable size were synthesized through a facile and simple solvothermal method.

High-resolution T MRI via renally clearable dextran nanoparticles with an iron oxide shell.

Contrast agents for magnetic resonance imaging (MRI) improve anatomical visualizations. However, owing to poor image resolution in whole-body MRI, resolving fine structures is challenging. Here, we report that a nanoparticle with a polysaccharide supramolecular core and a shell of amorphous-like hydrous ferric oxide generating strong T MRI contrast (with a relaxivity coefficient ratio of ~1.

Nanoscale Heat Transfer from Magnetic Nanoparticles and Ferritin in an Alternating Magnetic Field.

Recent suggestions of nanoscale heat confinement on the surface of synthetic and biogenic magnetic nanoparticles during heating by radio frequency-alternating magnetic fields have generated intense interest because of the potential utility of this phenomenon for noninvasive control of biomolecular and cellular function. However, such confinement would represent a significant departure from the classical heat transfer theory. Here, we report an experimental investigation of nanoscale heat confinement on the surface of several types of iron oxide nanoparticles commonly used in biological research, using an all-optical method devoid of the potential artifacts present in previous studies.

A magnetic resonance tuning sensor for the MRI detection of biological targets.

Sensors that detect specific molecules of interest in a living organism can be useful tools for studying biological functions and diseases. Here, we provide a protocol for the construction of nanosensors that can noninvasively detect biologically important targets with magnetic resonance imaging (MRI). The key operating principle of these sensors is magnetic resonance tuning (MRET), a distance-dependent phenomenon occurring between a superparamagnetic quencher and a paramagnetic enhancer.