In vitro studies on ultrasmall superparamagnetic iron oxide nanoparticles coated with gummic acid for T2 MRI contrast agent

Advances in Contrast Agents for Contrast-Enhanced Magnetic Resonance Imaging

INTRODUCTION

Magnetic resonance imaging (MRI) is a well-established medical invention in modern medical technology diagnosis. It is a nondestructive, versatile, and sensitive technique with a high spatial resolution for medical diagnosis. However, MRI has some limitations in differentiating certain tissues, particularly tiny blood vessels, pathological to healthy tissues, specific tumors, and inflammatory conditions such as arthritis, atherosclerosis, and multiple sclerosis. The contrast agent (CA) assisted imaging is the best possible solution to resolve the limitations of MRI.

METHOD

The literature review was carried out using the keywords, "MRI, T1&T2 relaxation, MRI CAs, delivery and adverse effects, classification of CAs." The tools used for the literature search were PubMed, Scopus, and Google Scholar.

RESULT AND DISCUSSION

The literature findings focus on MRI technique, limitations, and possible solutions. Primarily, the review focuses on the mechanism of CAs in image formation with detailed explanations of T1 and T2 relaxations, the mechanism of the MRI-CA image formations. This review presents the adverse effects of CA as well as available marketed formulations and recent patents to extent complete information about the MRI-CA.

CONCLUSION

MRI generates detailed visual information of various tissues with high resolution and contrast. The proton present in the biological fluid plays a crucial role in MR image formation, and it is unable to distinguish pathological conditions in many cases. The CAs are the best solution to resolve the limitation by interacting with native protons. The present review discusses the mechanism of CAs in contrast enhancement and its broad classification with the latest literature. Furthermore, the article presents information about CA biodistribution and adverse effects. The review concludes with an appropriate solution for adverse effects and presents the future prospective for researchers to develop advanced formulations.

Bacteria-assisted biogreen synthesis of radical scavenging exopolysaccharide-iron complexes: an oral nano-sized nutritional supplement with high in vivo compatibility

Microbial exopolysaccharides (EPSs) have recently served as an efficient substrate for the production of biocompatible metal nanoparticles (NPs) given their favorable stabilizing and reducing properties due to the presence of polyanionic functional groups in their structure. In the present work, Pantoea sp. BCCS 001 GH was used to produce EPS-stabilized biogenic Fe NPs as a complex through a novel biosynthesis reaction. Physicochemical characterization of the EPS-Fe complex was performed, indicating high thermal stability, desirable magnetic properties due to the uniform distribution of the Fe NPs with the average size of ∼10 nm and spherical shape within the EPS matrix. In addition, the in vivo toxicity of the EPS-stabilized Fe NPs was evaluated to investigate their potential for the treatment of iron deficiency anemia. Biological blood parameters and organ histology studies confirmed very high safety of the biosynthesized composite, making EPS-Fe a suitable candidate with an economical and environment friendly synthesis method for a wide spectrum of potential fields in medicine.

Rapid magnetic heating treatment by highly charged maghemite nanoparticles on Wistar rats exocranial glioma tumors at microliter volume

One of the most significant challenges implementing colloidal magnetic nanoparticles in medicine is the efficient heating of microliter quantities by applying a low frequency alternating magnetic field. The ultimate goal is to accomplish nonsurgically the treatment of millimeter size tumors. Here, we demonstrate the synthesis, characterization, and the in vitro as well as in vivo efficiency of a dextran coated maghemite (gamma-Fe(2)O(3)) ferrofluid with an exceptional response to magnetic heating. The difference to previous synthetic attempts is the high charge of the dextran coating, which according to our study maintains the colloidal stability and good dispersion of the ferrofluid during the magnetic heating stage. Specifically, in vitro 2 mul of the ferrofluid gives an outstanding temperature rise of 33 degrees C within 10 min, while in vivo treatment, by infusing 150 mul of the ferrofluid in animal model (rat) glioma tumors, causes an impressive cancer tissue dissolution.