Solvothermally Driven Mn Doping and Clustering of Iron Oxide Nanoparticles for Heat Delivery Applications.

Direct interactions between nanoparticles of Mn-doped magnetite or maghemite (clearly differentiated by Raman spectroscopy) grouped in spherical clusters minimize the effect related to their characteristic magnetic dead layer at the surface. Hence, the clustering process jointly with the manganese doping renders these ferrite nanostructures very attractive as displaying increased saturation magnetization, offering, consequently, outstanding values of the specific absorption rate (SAR) for heat delivery. The whole picture for bio-related applications has been considered, with issues related to magnetic manipulation, colloidal stability, and biocompatibility.

Interplay of chemical structure and magnetic order coupling at the interface between Cr2O3 and Fe3O4 in hybrid nanocomposites.

Hybrid nanocomposites based on ferrimagnetic (FiM) Fe3O4 and magnetoelectric antiferromagnetic (AFM) Cr2O3 nanocrystals were synthesized to offer a particular three-dimensional (3D) interface between the two oxides. This interface favours an intermixing process (demonstrated by combining Raman spectroscopy and magnetization measurements) that determines the final magnetic behavior.

Synergy effects of magnetic silica nanostructures for drug delivery applications.

This article presents a capable strategy of using hybrid nanostructures to improve the magnetic-based performance jointly with the internalization process into cells, for drug delivery applications. The promising combination stems from the concept of magnetic silica nanostructures, referring to magnetic nanoparticles of transition metal ferrites, coated with a silica (or hydroxyapatite) shell or included in a hollow silica nanostructure, such that they can offer a proper and controlled drug delivery. The synergy effects are brought on considering several characteristics; the magnetic properties of the transition metal ferrites as aggregates, the increased biocompatibility, the reduced toxicity, the porosity, the suitable chemical functionalization of silica and different effects such as local heating based on hyperthermia or other triggering effects for a time-space controlled drug delivery.

Photomultiplier tube artifacts on 67Ga-citrate imaging caused by loss of correction floods due to an off-peak status of one head of a dual-head γ-camera.

UNLABELLED: γ-cameras use flood-field corrections to ensure image uniformity during clinical imaging. A loss or corruption of the correction data of one head of a dual-head camera can result in an off-peak artifactual appearance. We present our experience with the occurrence of such an incident on a (67)Ga scan. METHODS: A patient was referred for a whole-body (67)Ga scan to evaluate for causes of neutropenic fever. Whole-body planar and static images of the head, chest, abdomen, pelvis, and lower extremities in multiple projections were obtained. RESULTS: Whole-body images showed decreased image quality on the anterior view obtained with detector 1 and an unremarkable posterior image obtained with detector 2. A problem with detector 2 was suspected, and additional static images were obtained after rotation of the detector heads. The posterior images taken with detector 1 showed photomultiplier tube outlines. The anterior images taken with detector 2 showed improved count and image quality. It was later found that the uniformity map for detector 2 had been lost and that this software malfunction led to the resulting imaging problem. CONCLUSION: When artifacts with an off-peak appearance are seen on scintigraphic images, evaluation of possible causes should include not only isotope window settings but also an incorrect or corrupted uniformity map.