A double-targeted magnetic nanocarrier with potential application in hydrophobic drug delivery

A double-targeted magnetic nanocarrier based with potential applications in the delivery of hydrophobic drugs has been developed. It consists of magnetite (Fe3O4) nanoparticles encapsulated in self-assembled micelles of the amphiphilic copolymer MPEG–PLGA [methoxy poly (ethylene glycol)-poly (d,l-lactide-co-glycolide)], and was fabricated using the solvent-evaporation technique. The magnetic nanocarrier has a very stable core–shell structure and is superparamagnetic. Its cytotoxicity was evaluated using the MTT assay with three cell lines—HeLa, MCF-7, and HT1080; it exhibited no cytotoxicity against any tested line at concentrations of up to 400 μg/mL after incubation for 24 h. Its cellular uptake was studied by Prussian blue staining and by fluorescence microscopy after encapsulating a fluorescent probe (hydrophobic quantum dots) into the nanocarrier. Finally, the magnetic targeting property of the magnetic nanocarrier was confirmed by an in vitro test. Overall, the results obtained demonstrate the potential of the double-targeted nanocarrier for the intracellular delivery of hydrophobic drugs.