Lipid Nanoparticles: Tumor-targeting Nanocargos for Drug and Contrast Agent Delivery

A new technology for the encapsulation of lipophilic molecules -both drugs and contrast agentshas been developed, based on oil-in-water nanoemulsions. Physicochemical characterizations of the nanoparticles evidence highly stable lipid nanoemulsions with amorphous core of temperatureand compositiontunable viscosity. Particles display low in vitro cytotoxicity (IC50 > 300 μg/mL of lipids), and high tolerance in vivo. They can be efficiently loaded with hydrophobic to amphiphilic molecules, such as fluorescent dyes for tumor labeling, photosensitizers for phototherapy, or chemotoxic drugs. The presence of PEGylated surfactants in the particle coating ensures a good in vivo stealthiness, as assessed by their biodistribution recorded using fluorescence imaging and radioactivity counting (C and H particle labeling). The lipid nanoparticles can moreover be functionalized by tumortargeting ligands, such as the cRGD peptide, to improve specific tumor cell accumulation.