𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Synthesis of Iron Oxide Nanoparticles Used as MRI Contrast Agents: A Parametric Study

✍ Scribed by Lucia Babes; Benoı̂t Denizot; Gisèle Tanguy; Jean Jacques Le Jeune; Pierre Jallet


Publisher
Elsevier Science
Year
1999
Tongue
English
Weight
190 KB
Volume
212
Category
Article
ISSN
0021-9797

No coin nor oath required. For personal study only.

✦ Synopsis


Colloidal iron oxides play an important role as magnetic resonance imaging (MRI) contrast agents. The superparamagnetic particles actually used are constituted by solid cores (diameter of 5-15 nm), generally coated by a thick polysaccharidic layer (hydrodynamic radii of 30-100 nm), and formulated by direct coprecipitation of iron salts in the presence of polymeric material. To better control the synthesis, we attempted to formulate new stable uncoated superparamagnetic nanoparticles. Colloids were generated by coprecipitation of an aqueous solution of iron salts and tetramethylammonium hydroxide (TMAOH) solution. The influence of parameters such as media composition, iron media, injection fluxes, Fe and TMAOH concentrations, temperature, and oxygen on size, magnetic and magnetic resonance relaxometric properties, and colloidal stability of particles were evaluated. We have determined the relative importance of these parameters as well as the optimal conditions for obtaining uncoated stable particles with an average size of 5 nm and interesting relaxivities. The interpretation of the observed limits takes into account diffusibilities of reactants and product, feeding rates of reactants, and surface properties of nanoparticles. A model of synthesis, related to spontaneous emulsification of suspensions, is proposed. Copyright 1999 Academic Press.


📜 SIMILAR VOLUMES


Investigation of the magnetic properties
✍ D. Pouliquen; H. Perroud; F. Calza; P. Jallet; J. J. Le Jeune 📂 Article 📅 1992 🏛 John Wiley and Sons 🌐 English ⚖ 756 KB

## Abstract Superparamagnetic iron oxide particles, a new class of contrast agents for MRI, are extremely good enhancers of proton relaxation. However, the development of such particle systems has resulted in a wide range of preparations whose physico‐chemical properties differ greatly. We have con

Superparamagnetic iron oxide MION as a c
✍ Chris D. Constantinides; J. Rogers; D.A. Herzka; F.E. Boada; D. Bolar; D. Kraitc 📂 Article 📅 2001 🏛 John Wiley and Sons 🌐 English ⚖ 166 KB

## Abstract An intravascular iron‐based contrast agent was used as a sodium (^23^Na) MRI __T__~2~ relaxant in an effort to suppress the blood signal from the ventricular cavities in normal and infarcted canine myocardium in vivo. ^23^Na MRI signal decreases in blood were attributed to decreases in

MRI in focal liver disease: A comparison
✍ Patricia J. Mergo; John D. Engelken; T. Helmberger; Pablo R. Ros 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 824 KB

The purpose of this study was to compare small and ultrasmall superparamagnetic iron oxide particles (SPIO and USPIO, respectively) as MR contrast agents for the evaluation of focal hepatic disease. In two different patient groups (SPIO [n = 53], USPIO [n = 27]), with focal liver disease (metastases

Assessment of a superparamagnetic iron o
✍ Thomas A. Kent; Michael J. Quast; Barry J. Kaplan; Robert S. Lifsey; Howard M. E 📂 Article 📅 1990 🏛 John Wiley and Sons 🌐 English ⚖ 441 KB

## Abstract We have applied a superparamagnetic iron oxide formulation (AMI‐25, Advanced Magnetics, Inc., Cambridge, MA) to image the cerebral vasculature. Contrast‐enhanced images of normal anesthetized rats demonstrated excellent gray/white matter differentiation, consistent with known difference

Ultrasmall particulate iron oxides as co
✍ Géraldine Le Duc; Luce Vander Elst; Jean Marie Colet; Alain Roch; Pierre Gillis; 📂 Article 📅 2001 🏛 John Wiley and Sons 🌐 English ⚖ 234 KB

## Abstract Long‐distance effects of a superparamagnetic contrast agent (AMI227) were investigated by phosphorus‐31 NMR spectroscopy at 7.05 Tesla. In an initial methodological approach, the effects observed on phantoms were compared to the results of theoretical calculations. In a second step, the