Design of PLGA Based Nanoparticles for Imaging Guided Applications

Abstract

An amphiphilic Gd(III) complex has been efficiently loaded in polylactic-co-glycolic acid nanoparticles (PLGA-NPs) to yield a novel, high sensitive magnetic resonance imaging (MRI) contrast agent for imaging guided drug delivery applications. As the Gd(III) complex is soluble in organic solvents, the nanoparticles were prepared as oil/water emulsions. PLGA-NPs were stable, in buffer, for more than 1 week without any release of the incorporated agents. The millimolar relaxivity of the Gd(III) complex incorporated in the particles (140 nm diameter) was of 21.7 mM(-1) s(-1) at 21.5 MHz, a value that is about 5 times higher than that observed with the commercially available contrast agents used in clinic. The relaxometric efficiency of these particles resulted inversely proportional to the particle size measured by dynamic light scattering. The high stability and sensitivity of PLGA-NPs allowed their accumulation in vivo in murine melanoma xenograft as shown in the corresponding MR images. Once loaded with drug and contrast agents, PLGA nanoparticles can be proposed as efficient theranostic MRI agents.

Mesoporous silica nanoparticles functionalized with fluorescent and MRI reporters for the visualization of murine tumors overexpressing αvβ3receptors

“…For example, nanomaterials, such as dendrimers, 5 polymers, [6][7] proteins, 8 gold 9 and silica [10][11] nanoparticles have been applied as slowly moving carriers for Gd(III)-complexes. One of the most significant limitation of the currently reported nanosized T 1 -CAs is their large overall size (>100 nm) that markedly affect their in vivo distribution as they are quickly cleared by the reticuloendothelial system (RES).…”

Innovative Design of Ca-Sensitive Paramagnetic Liposomes Results in an Unprecedented Increase in Longitudinal Relaxivity

“…This product exhibited specific properties that already indicated its amphiphilic nature. Namely, despite good solubility, the resonances of carbons from the SCA moiety could not be seen in the 13 C NMR spectra when using chloroform-d 1 or methanol-d 4 as solvents, but only when using dimethylformamide-d 7 . We explain this by the micelle formation in the former solvents, which restricts the motion of SCA moieties, leading to shortening of T 2 relaxation times, broadening of signals and their elimination.…”

Ferritin Decorated PLGA/Paclitaxel Loaded Nanoparticles Endowed with an Enhanced Toxicity Toward MCF-7 Breast Tumor Cells

“…PLGA-NPs were obtained by the o/w emulsion solvent extraction method. The organic phase was prepared by dissolving PLGA or PLGA-NHS and Gd-DOTAMA complex in chloroform 30 . The water phase was a poly vinyl alcohol (PVA) aqueous solution.…”