Superparamagnetic iron oxide nanoparticles as a liver MRI contrast agent: Contribution of microencapsulation to improved biodistribution

Formulation of Superparamagnetic Iron Oxides by Nanoparticles of Biodegradable Polymers for Magnetic Resonance Imaging

“…Similar work carried out by Pouliquen et al reported a decrease in MR relaxivities of the IOs in their polymeric nanoparticle formulation. [29] Since they did not conduct any r 2 * measurement, one explanation could be that their results were not accounted for by either MAR or SDR. Another possible reason for their decreased relaxivities could be the increased distance between the IOs in the polymeric matrix and the water molecules that had penetrated into the polymer matrix.…”

“…[20,21] The biodegradable polymers that are used most often for formulation of therapeutic agents are poly(D,L-lactide) (PLA) and poly(D,L-lactide-co-glycolide) (PLGA), which are FDA approved polymers for clinical application. Formulation of IOs by biodegradable polymeric particles has been developed in the literature, [21][22][23][24][25][26][27][28][29] where the cytotoxicity issue has been addressed, the influence of physicochemical properties such as size and surface morphology and chemical composition of polymer matrix on the iron entrapment efficiency has been investigated, and magnetization measurements have been conducted. Few reports, however, contained MRI measurements to determine the magnetization and relaxivities of the IOs formulated in the biodegradable polymeric particles.…”

Magnetic Nanoparticles and Their Applications

“…[206] these magnetic nanoparticles have been used to detect specific cells and their movement. [207][208][209][210][211][212][213][214][215] The practical limit of magnetic nanoparticle detection based on T 2 * measurements can be estimated using the results obtained in prior experiments with NMR micro-coils. [216] Lauterbur and co-workers estimated [217] that a single magnetic particle is detectable in a volume 50 times its diameter.…”

Magnetically responsive microparticles for targeted drug and radionuclide delivery.

“…The drug is released from the carrier in a controlled manner and then exerts its pharmacological action at cellular and/or subcellular level in the tumor tissue without critically affecting the survival of normal tissue (Widder et al 1978). This approach has since been studied by many other authors (Tsyb et al 1983, Sako and Hirota 1986, Stark et al 1988, Pouliquen et al 1989, Gupta and Hung 1993, outlining the possibility of targeting magnetic microcapsules, liposomes and ghost cells containing various cytotoxic drugs. More recent developments on magnetic targeting of radiotherapeutic particles are discussed by Häfeli et al (2001).…”