Modified TPGS Nanoparticles By Folic Acid And Disulfide Bond For Overcoming Multidrug Resistance Of Hepatocellular Carcinoma

Object The purpose of this study was to investigate the ability of DOX-loaded Tocopheryl polyethylene glycol succinate(TPGS)nanoparticles to overcome multidrug resistance in the treatment of drug-resistant liver cancer.We conducted in vitro cell experiments to confirm the therapeutic effect of this nanoparticle on Hep G2-ADM cells,to detect its cytotoxicity and targeting to Hep G2-ADM cells,and to conduct in vitro MR imaging,so as to prove that it can be a new multi-functional image contrast agent.Methods By introducing folic acid(FA)and disulfide bond(-SS-)into vitamin E polyethylene glycol monoplatinum ester(TPGS),this will enable the preparation of the nano-polymer FA-SS-TPGS to be environmentally responsive and targeted.At the same time,due to the amphiphilic nature of the nanopolymer,hydrophobic superparamagnetic iron oxide(SPIO)and DOX(DOX)can be coated in the nanoprobe to be polymerized into diagnostic and therapeutic nanoparticles FATPGS/SPIO and FA-SS-TPGS /SPIO.The characterization of FA-TPGS@DOX /SPIO,FA-SS-TPGS@DOX /SPIO: the particle size distribution of the probe was observed under a projection electron microscope,and the inclusion rate of hydrophobic superparamagnetic iron oxide(SPIO)and DOX was tested.Finally,MR imaging was used to measure the T2 weighting,so as to measure the different relaxation rates of the probe.In vitro cell experiments,the biocompatibility experiments of TPGS/SPIO,FATPGS/SPIO,FA-SS-TPGS/SPIO blank materials were carried out by CCK-8 method,and the biological safety of blank materials was confirmed.Prussian blue staining was then performed to confirm that the probe could be targeted into the cells.Then the materials loaded with DOX were detected by CCK-8 method,and the absorbance value was detected on the enzyme marker to obtain the cell survival rate and verify the cytotoxicity of the materials.In order to further confirm the cytotoxicity,we also did Calcein-AM /PI staining.We then analyzed the cell uptake and distribution by DAPI staining and flow cytometry to confirm the targeting of micelles.Finally,MR imaging was performed to compare micelle T2.Results 1.According to the DLS test,the average particle size of blank FA-SS-TPGS micelles is about 95.6 nm,and that of FA-SS-TPGS@DOX /SPIO micelles is about 134.6 nm.At the same time,FA-SS-TPGS prepared by electron microscopy has a high load capacity on adriamycin and SPIO.At the same time,FA-SS-TPGS@DOX /SPIO nanoparticles make it easier to release DOX.2.In vitro MR imaging results: with the increase of Fe ion concentration,T2 signals of TPGS/SPIO,FA-TPGS/SPIO and FA-SS-TPGS /SPIO probes would gradually decrease.Prove that the probe can be used for T2 contrast.3.Biocompatibility experiment: TPGS,FA-TPGS,FA-SS-TPGS blank vector has low toxicity to Hep G2-ADM cells and good biocompatibility to Hep G2-ADM cells,so it can be used for further experiments.4.Cell uptake assay: Prussian blue staining assay confirmed that TPGS,FATPGS,FA-SS-TPGS targeting probes can be absorbed by cells.DAPI and flow cytometry showed that TPGS@DOX,FA-TPGS@DOX,FA-SS-TPGS@DOX could be absorbed by Hep G2-ADM cells and distributed in the cytoplasm,while free DOX could hardly enter Hep G2-ADM cells.5.Cytotoxicity experiment results: TPGS @ DOX,FA TPGS @ DOX,FA-SS TPGS @ DOX targeted probe are prepared into different concentration of solution.After co-incubation with Hep G2-ADM cells for 24 hours,the cell survival ratemeasured by CCK-8 method was in inverse proportion to the drug concentration developed.When the concentration of the drug increased,the inhibitory effect of the drug on Hep G2-ADM cells was more significant.However,free DOX has no obvious inhibitory effect on the growth of Hep G2-ADM cells.The results of Calcein-AM /PI staining showed that the higher the drug concentration,the stronger the killing effect on Hep G2-ADM cells.At the same time,TPGS @ DOX,FA TPGS @ DOX,FA-SS TPGS @ DOX are more lethal than free DOX.Conclusion In this study,DOX-loaded Tocopheryl polyethylene glycol succinate(TPGS)nanoparticles were prepared for integrated diagnosis and treatment to overcome the multi-drug resistance of liver cancer cells.The prepared nanoparticles have good biocompatibility and targeting,good lethality to drug-resistant hepatocellular carcinoma cells and MR development,so they have a good application prospect...