Preparation Of Nedaplatin-Carboxylated Magnetic Mesoporous Silica Nanoparticles And Preliminary Study On The Effect Of SK-MES-1 Cells In Combination With Hyperthermia

Purpose:This study use nedaplatin?NDP?as model drug,carboxyl-modified magnetic mesoporous silica?MMSNs-COOH?as carrier to construct NDP-MMSNs-COOH.Preparation and characterization and the influences against lung squamous carcinoma cell SK-MES-1 and related mechanisms were studiedd when NDP-MMSNs-COOH combined with hyperthermia.Methods:In this study,Iron oxide?Fe₃O₄?nanoparticles was prepared with chemical precipitation at first.The Fe₃O₄ nanoparticles was coated with the silica through sol-gel method.Next,surface active agent was removed with the mixture of ammonium nitrate and ethanol solution through ion exchange method.Therefore,Fe₃O₄/mSiO₂ nanoparticles?represented by MMSN?which have mesoporous structure were obtained.Fe₃O₄/mSiO₂ nanoparticles were modified by amino and carboxyl and become MMSNs-NH₂ and MMSNs-COOH.The structure and morphology of the carrier were characterized by infrared,transmission electron microscopy,mesoporous analysis and magnetic test.The warming effect of the 808laser on the carrier material were investigated.NDP,which act as model drug,was invested the influence of solvent type,different delivery methods,reaction time and different functional groups on the drug loading and entrapment efficiency through the single factor.The optimal drug prescription and craft were determined.High performance liquid chromatography?HPLC?was used for the determination of NDP drug content.The drug release condition of NDP apis and NDP-MMSNs-COOH respectively under the condition of 37?and 43?were studied.In the anti-tumor antivity experiments in vitro,we use SK-MES-1 pulmonary squamous cancer cells as model tumor cells.MTT assay was used to detect the cytotoxicity of NDP APIs,preparations and carriers at the same time analysis anticancer efficacy of the NDP-MMSNs-COOH and NDP apis in combination with magnetic hyperthermia?by 808 laser irradiation?in vitro through the cytotoxic experiment.The carrier was labeled with FITC and the uptake of the cells were detected by fluorescence microscopy and flow cytometry,respectively.Combing NDP drug and NDP-MMSNs-COOH and magnetic hyperthermia,the effects of cell cycle and apoptosis and the mechanism of action on lung squamous cell carcinoma cell SK-MES-1 were investigated.Results:The carrier were characterized:transmission electron micrographs showed that the particle size of the magnetic core is 5¹5 nm particles,MMSNs and MMSNs-COOH are particles to coat magnetic cores with a particle size of 60 to 100nm,which have a mesoporous structure with a diameter of 5nm approximately.Magnetic test indicates that the saturation magnetization value of Fe₃O₄ and MMSNs nanoparticles is 58 emu/g and 18 emu/g.N₂ adsorption and desorption curve indicates that the shape of the curve meets the type IV adsorption and stripping isotherm,specific surface area of magnetic mesoporous silica nanoparticles is 753.30m²/g,pore volume of 1.03 cm³/g.The MMSNs,MMSN-NH₂,and MMSNs-COOH were irradiated for 3 min by 808 lasers,the carrier temperature was increased by9.9°C,9.9°C,and 12.4°C,respectively.Drug loading conditions were studied and optimized for the carrier.Finally we choose anhydrous ethanol as solvent,carboxyl modified mesoporous silica MMSNs-COOH as the carrier,with the method of exceeding 15 min to load NDP.We selected three different functional groups carrier to take medicine research,the results indicated that the encapsulation efficiency of MMSNs was 93.45%and drug loading was 62.3%,Which achieved higher entrapment efficiency and drug loading.The results of drug release at 37°C and 43°C in vitro showed that it had a sustained release effect;when the drug release time reached 12 h,the cumulative release rate was 82.34%and 88.95%,both of which could reach 80%or more.Increase in temperature promoted drug release.The anti-tumor activity of NDP in vitro were studied.SK-MES-1 cells were more sensitive to nedaplatin When NDP APIs were combined with HT.IC50 values reduce from 116.62?g/mL to 79.84?g/mL after nedaplatin combined with hyperthermia for 24 h.IC50 values decreased from 94.46?g/mL to 70.86?g/mL after NDP-MMSNs-COOH combined with hyperthermia.MMSNs-COOH had better cell uptake effect.Cycle and apoptosis experiments results showed that NDP-MMSNs-COOH combined with hyperthermia can induce cell S phase arrest,leading to apoptosis.The apoptosis rate of NDP api and preparations increased from1.5%and 4.1%to 5.2%and 12.2%after combined with hyperthermia,respectively.Conclusion:The carboxyl-modified magnetic mesoporous silica for drug loading has higher entrapment efficiency and drug loading.Hyperthermia combined with NDP-MMSNs-COOH can increase inhibitory effect,apoptosis and ingestion against lung squamous carcinoma cell SK-MES-1.This study provides data references for the study of NDP-magnetic mesoporous silica preparations for lung squamous cell carcinoma.