Magnetic Nanocarrier Containing 68 Ga–DTPA Complex for Targeted Delivery of Doxorubicin

In the present study, a multifunctional pH-sensitive nanocarrier was prepared for targeted drug delivery in chemotherapy with potential usage in magnetic and nuclear medicine imaging. The Fe3O4@SiO2 core–shell nanoparticles were initially prepared, functionalized with aminopropyltriethoxysilane (APTES), grafted with diethylenetriaminepentaacetic acid ligand (DTPA), and conjugation with an anti-cancer drug, doxorubicin (DOX). DOX was covalently linked via an amine group with carboxylic acid groups of DTPA. The amide bonds between the drug and the ligand were enabled to cleave in acidic pH (i.e. 5.5), and subsequently, the drug was released in slow fashion (85 wt% within 4 h). The superparamagnetic core in the carrier allows the targeted delivery of drug to the cancer tumor sites using external magnetic fields. Magnetic nanocarriers could also be used in magnetic resonance imaging (MRI). Radiolabelling of the carrier was carried through a chelation of Ga(III) ion by DTPA that can be used for positron emission tomography. It is expected that the multi-modal nanocarrier, Fe3O4@SiO2–APTES–DTPA–Ga–DOX, can have theranostic (therapeutic and diagnostic) applications. Fe3O4@SiO2–APTES–DTPA–Ga–DOX nanocarrier is produced for pH-controlled release drug delivery system. The carrier can be used in medical diagnosis due to its magnetic and radiolabeling features.