The Cellular Uptake Mechanism Of Metal Organic Aerogel MOG-100(Fe) As Drug Carrier

Metal Organic Frameworks(MOFs) are mainly composed of metal ions or metal clusters and organic acid ligand through chemical coordination, the porous crystallization structure are formed by self-assembly. They have many advantages,such as porosity, large surface area and so on. They are often used in gas adsorption and separation, catalysis, wastewater treatment, electrochemical sensors, etc. For the past few years, some reports have showed their application in biomedical fields,such as a drug carrier, biomedical imaging, etc. However, when MOFs act as drug carrier, the high drug-loading effiencicy only happens in some MOFs, which confines their application as drug carrier. In recent years, a new type of material,metal organic aerogels(MOGs) begin to attract people’s attention. They are formed by adding metal ions into supramolecular organic gel, show half solid state. Being different from the traditional MOFs, MOGs has the nature of both solid and liquid at the same time. When they act as catalyst, they could show dual properties as heterogeneous catalysts and homogeneous catalysts; and when there are same metal ions and organic ligands, the reaction conditions are different, the formed MOGs would have different constructures.Metal organic aerogel material MOG-100(Fe) has many advantages, such as high porosity, big specific surface area, diverse topology structures, adjustable aperture and so on, it has the potential application as drug carrier. But the feasibility of acting as drug carrier and the specific cellular uptake mechanism have not yet been reported. So the main research contents are as follows:1. Research on carrier properties. At First, the feasibility of MOG-100(Fe) as a drug carrier was examined: The experiments were processed mainly in MCF-7 cells,the cell line was used as vitro model, MTT method was used to determine the effects of MOG-100(Fe) on tumor cell proliferation. Also the effect of MOG-100(Fe) on MCF-7 cell apoptosis and cell cycle were studied. Then using MOG-100(Fe) load paclitaxel(PTX) to investigate their antitumor activities. And FITC was used as the model drug to exam the slow release effect of MOG-100(Fe). The results showedthat MOG-100(Fe) had no significant effect on cell proliferation and no much impact on normal cell cycle, at the same time it almostly didn’t induce cell apoptosis.The antitumor activity in vitro results showed that MOG-100(Fe) had a slow-release effect on drugs, extended the drug action time, improved the antitumor activity.2. The investigation of cellular uptake mechanism. Coumarin 6 was used as a model to elaborate the cellular uptake mechanism of MOG-100(Fe). First of all,MOG-100(Fe)-Coumarin 6 nano-compounds were prepared, Flow cytometry was applied to analyse the cellular uptake properties of MOG-100(Fe)-Coumarin 6, at the same time, fluorescence microscope was used to observe the intracellular distribution. Then the cellular uptake and elimination kinetics of MOG-100(Fe)-Coumarin 6 were investigated. At last, the interaction of MOG-100(Fe) and cellular total protein was studied, then LC-MS was used to analyse the specific proteins which had interaction with MOG-100(Fe), the uptake mechnism was further elaborated on protein level. Results showed that after Coumarin 6 was absorbed into MCF-7 cells, the intracellular drug content increased gradually at the first time, as time extended, the intracellular drug content gradually reduced; as to MOG-100(Fe)-Coumarin 6 group, with the extension of time, the intracellular drug content continued to increase. At the same time, saturation inhibition experiments and endocytosis inhibitors experiments were used to validate the specific cellular uptake mechanism of MOG-100(Fe). Results indicated that the MOG-100(Fe) was mainly ingested by clathrin-mediated endocytosis pathway into the cells, to a certain extent, the uptake was energy- and dosage-dependent process.The cellular total protein was extracted from MCF-7 cells by cell lysis method, then cellular total protein incubated with MOG-100(Fe), SDS-PAGE electrophoresis assays then demonstrated that MOG-100(Fe) could interact with cellular total protein, then LC-MS was used to analyze the specific proteins with MOG-100(Fe).