Nanoscale Metal-Organic Frameworks Decorated with Graphene Oxide for Magnetic Resonance Imaging Guided Photothermal Therapy

Imaging-guided photothermal therapy (PTT) provides an attractive way to treat cancer. A composite material of a nanoscale metal-organic framework (NMOF) and graphene oxide (GO) has been prepared for potential use in tumor-guided PTT with magnetic resonance imaging (MRI). The NMOFs containing Fe3+ were prefabricated with an octahedral morphology through a solvothermal reaction to offer a strong T-2-weighted contrast in MRI. Then the NMOFs were decorated with GO nanosheets, which had good photothermal properties. After decoration, zeta-potential characterization shows that the aqueous stability of the composite material is enhanced, UV/Vis and near-infrared (NIR) spectra confirm that NIR absorption is also increased, and photothermal experiments reveal that the composite materials express higher photothermal conversion effects and conversion stability. The fabricated NMOF/GO shows low cytotoxicity, effective T-2-weighted contrast of MRI, and positive PTT behavior for a tumor model in vitro. The performance of the composite NMOF/GO for MRI and PTT was also tested upon injection into A549 tumor-bearing mice. The studies in vivo revealed that the fabricated NMOF/GO was efficient in T-2-weighted imaging and ablation of the A549 tumor with low cytotoxicity, which implied that the prepared composite contrast agent was a potential multifunctional nanotheranostic agent.