Fabrication And Drug Delivery Properties Of Core-Shell Metal-Organic Frameworks

BackgroundMetal-organic frameworks?MOFs?are a new generation of porous materials composed of metal ions linked by multitopic organic ligands,forming extended network structures.The structure and composition of MOFs can easily be tuned by the infinite possible combination of metal subunits and constitutive organic ligands,leading to thousands of MOFs with unique features.In the past few years,a number of works have demonstrated the great potential of MOFs nanoparticles at the preclinical level for biomedical applications.The size of MOFs is critical for their various applications.Nanomaterials,due to their smaller particle size,can indeed improve the drug delivery performances.ObjectiveTo date,a few pioneering works demonstrated the promise of magnetic MOFs for targeted drug delivery have been reported.Although these reported MOFs-based magnetic porous carriers exhibited high drug loading capacity and excellent drug release behavior,the size of them is quite big.In this dissertation,we describe a simple strategy for the designing and synthesizing nanosize MOFs-based magnetic core-shell nanocarriers,which show a novel enhanced drug delivery property.The obtained results will be helpful for the fabrication of high-performance magnetic core-shell porous nanocarriers in targeted drug delivery.MethodsFe3O4@MIL-100?Fe?magnetic NPs were successfully prepared by a facile step-by-step assembly method.An nontoxic MIL-100?Fe?@SiO₂ nanoparticles have been synthesized by a versatile sol-gel strategy.The concentration of the released Ibuprofen?IBU?in each sample was measured by UV-vis spectroscopy.The amount of released GA was analyzed by the high performance liquid chromatography?HPLC?.The antioxidant activity of free and encapsulated GA was evaluated by the DPPH method.Results1.In this work,a nano-sized MOFs-based magnetic core-shell nanoparticle?NP?has been successfully prepared by a facile step-by-step assembly method designing for targeted drug delivery.The diameter of Fe3O4@MIL-100?Fe?magnetic NPs are around 240 nm and the SiO₂ shell thickness is about 50 nm.By the combination of the high porosity of MOFs shell and the magnetic characteristics of Fe₃O₄ core,the newly fabricated NPs exhibited an excellent drug delivery effect.2.Significantly,the anti-inflammatory drug Ibuprofen?IBU?was effectively loaded on the magnetic NPs with a loading capacity of 0.31 g g^-1,and it took as long as 70 h to release IBU completely in PBS buffer solution at 37 ^oC.The amount of GA loaded in the MIL-100?Fe?@SiO₂ is shown to be 0.23 g g^-1,and it took as long as 85 h to complete GA release in PBS solution at 37°C.3.An nontoxic MIL-100?Fe?@SiO₂ nanoparticle has been synthesized by a versatile sol-gel strategy.The silica shell as the coating can enhance biocompatibility and water dispersibility.4.The antioxidant activity of MIL-100?Fe?@SiO₂-GA results suggest that the encapsulation of the GA in the pores of MOFs could effectively protect GA from degradation in alkaline solutions.The loaded GA within the MIL-100?Fe?@SiO₂ showed an enhancement of killing the C6 cell death.ConclusionThe prepared MIL-100?Fe?@SiO₂ nanoparticles are potential carrier for drugs like green tea catechins and showed an excellent biocompatibility and effective performance in the antioxidant and anticancer activity.The newly fabricated nano-sized MOFs-based magnetic NPs might be promising candidates for targeted drug delivery applications.