A Type Of Nano-drug Preparation Against Hepatoblastoma And Its Anti-tumor Cell Effect

Objective:To prepare a type of nanomedicine preparation containing cisplatin,an anti-hepatoblastoma chemotherapy drug.The nanomedicine preparation can passively target the liver tumor site through the"long circulation"in the blood circulation and the"Enhanced permeability and retention（EPR）effect",and release the drug in the weak acid microenvironment and promote the endocytosis.A series of characterization and functional tests were carried out to explore the relationship between hydrophobic substitution degree and acid-sensitive linkage arm and the structure and function of drug-carrying nanoparticles.Methods:1.The synthesis of different hydrophobic substitution degree of Polyethylene glycolated hydrophobic modified amino-pullulan（PEG-CHPNH₂）polymer,acid/non-acid sensitivity PEG-CHPNH₂polymer,preparation into blank nanoparticles,respectively.Using infrared spectrometer analysis of the structure,magnetic resonance analysis of hydrophobic substitution degree,dynamic light scattering（DLS）detect potential and particle size,transmission electron microscopy（TEM）observation of morphology.2.Drug-carrying nanoparticles were prepared by loading cisplatin into three kinds of polymers.DLS was used to detect the potential and particle size.TEM was used to observe the morphology,standard curve of cisplatin was made to calculate the encapsulation rate and drug loading,and the drug release rate at different p H was measured by ultraviolet spectrophotometer.3.The anti-tumor cell effect of nanoparticles was studied by cell viability assay and cell uptake test.Results:1.Acid-sensitive PEG-CHPNH₂（1）,acid-sensitive PEG-CHPNH₂（2）and acid-sensitive PEG-CHPNH₂nanoparticles were successfully prepared,and the hydrophobic substitution degrees were 5.41%,3.58%,5.23%,respectively.DLS measurement results show that all have positive charge,particle size:118.9nm,166.9nm,118.7nm.TEM results showed that all of them were uniformly spherical.2.Three kinds of PEG-CHPNH₂blank nanoparticles were successfully loaded with cisplatin.DLS measurement results show that all have positive charge,particle size:270nm,265.5nm,281.9nm.TEM results show that all of them are uniformly spherical.The drug loading was（63.78±2.03）%,（57.03±1.04）%,（55.08±1.62）%,and the encapsulation rate was（68.12±1.09）%,（60.48±2.17）%,（58.29±1.25）%,respectively.All the three drug-loaded nanoparticles had sustained release effect.The drug release rates were 60.45%,66.78%and 57.24%at p H 7.4 for 48hours,and 75.42%,82.44%and 70.25%at p H 6.8 for 48 hours.3.Cell viability assay results showed that the cell survival rates of free cisplatin and three drug-loaded nanoparticles at the maximum drug concentration for 48h were 42.30%,37.53%,40.17%and 53.34%,indicating that acid-sensitive PEG-CHPNH₂（1）drug-loaded nanoparticles had the strongest cytotoxicity.The cell uptake experiment results showed that the cell uptake rate of acid-sensitive PEG-CHPNH₂（1）drug-loaded nanoparticles was the highest,and the cell uptake rate of non-acid-sensitive PEG-CHPNH₂drug-loaded nanoparticles was the lowest.Conclusion:1.The PEG-CHPNH₂drug-loaded nano system was successfully prepared,which had high drug-loading capacity and encapsulation efficiency for cisplatin.The larger the water substitution degree of nanoparticles,the smaller the particle size,but the hydrophobic substitution degree has little effect on the particle size of drug-loaded nanoparticles.2.The loading capacity of high hydrophobic substitution degree nanoparticles is good,while the slow release capacity of low hydrophobic substitution degree nanoparticles is good.The highly hydrophobic substituted acid-sensitive nanoparticles were more cytotoxic and more easily absorbed by Hu H-6 cells.