Construction And Anti-tumor Evalution Of Evaluation Of Rhein Prug Micelles Based On Pluronic

The research content of this project is as follows:Preparation of Pluronic SS-RH polymer prodrugs containing disulfide bonds.Pluronic SS-RH polymer prodrug was prepared by activating the hydroxyl groups at both ends of Pluronic through carbonyl diimidazole(CDI),connecting cysteamine containing disulfide bonds at both ends of Pluronic,and finally connecting RH to the amino groups at both ends of modified Pluronic through amide reaction.The successful synthesis of Pluronic SS-RH polymer prodrug was demonstrated by characterizing its structure through nuclear magnetic resonance hydrogen spectroscopy,infrared spectroscopy,ultraviolet spectroscopy,and other methods.Preparation of Pluronic-SS-RH prodrug micelles using solvent evaporation method.The average particle size of the prepared prodrug micelles is 182.4 ± 4.7 nm,PDI is 0.130 ± 0.42,and Zeta potential is-10.5 m V.The drug content of the prodrug micelles is 5.7%.Transmission electron microscopy shows that the precursor micelles are spherical in shape,uniform in size,and uniformly dispersed without agglomeration.The CMC of the prodrug micelles is 46.49 μ G/ml,much lower than the individual Pluronic forming micelle CMC.The prodrug micelles were stored for 15 days without significant changes in particle size and PDI,indicating good storage stability.After diluting the current drug micelle 50 times,the particle size of the precursor drug micelle remains within 220 nm,indicating good dilution stability.The cumulative release rate of Pluronic SS-RH prodrug micelles reached 73% under the condition of p H=5.5 GSH and 20 m M,which is significantly higher than p H=5.5 GSH and is 2 μ The cumulative release rate under the condition of M indicates that Pluronic SS-RH prodrug micelles have redox sensitivity.The Pluronic SS-RH prodrug micelles were incubated in the presence of GSH for 24 hours,and the particle size increased from 195 nm to 450 nm.The PDI increased from 0.186 before incubation to 0.420.This further proves that Pluronic-SS-RH prodrug micelles have redox sensitivity.The hemolysis rate of blank material Pluronic is less than 5% within 1mg/ml;After incubating blank material Pluronic with human normal liver cell line L-02 and human colon cancer cell line SW-480 for 48 hours,the cell survival rate was greater than 80%.The cytotoxicity and hemolysis experiments of the blank material showed good biocompatibility.In vitro anti-tumor experiments were conducted using human colon cancer cells HCT-116,SW-480,and SW-620 as model cells.The toxicity of free RH and Pluronic SS-RH prodrug micelles to three types of colon cancer cells was investigated using MTT method.The results showed that the free RH and Pluronic SS-RH prodrug micelles exhibited drug concentrations ranging from 10 to 125 μ Within the range of M,the cell survival rate continuously decreases,showing a significant concentration dependence.As the administration time prolonged,the cell survival rate of the free RH and Pluronic SS-RH prodrug micelles groups showed a significant downward trend.The cytotoxicity of the free RH and prodrug micelles to three types of colon cancer cells showed a significant time-dependent effect.And the inhibitory effect of Pluronic SS-RH prodrug micelles on tumor cells is significantly stronger than that of free RH.The results of cytotoxicity experiments indicate that the preparation of RH into redox sensitive micelles can significantly increase the drug’s toxicity to tumor cells.By preparing the Pluronic SS-RH prodrug micelles loaded with coumarin-6 and observing the cellular uptake of the prodrug micelles under a fluorescence inverted microscope,the results showed that the initial uptake of the prodrug micelles loaded with coumarin-6 was significantly lower than that of coumarin-6.However,after 6 hours,the prodrug micelles could achieve the same uptake as the free coumarin-6,proving that the preparation of RH into prodrug micelles did not affect the uptake of RH by tumor cells.This article establishes a method for the determination of RH content in cell fluid by high-performance liquid chromatography and conducts methodological validation on this analysis method.The results indicate that the established method for determining RH content in cell fluid has good specificity,precision,and accuracy.By using the established assay method,the intracellular RH content during the drug uptake and drug elimination stages was determined for cellular pharmacokinetic studies.The results showed that the drug half-life(t1/2),area under the drug time curve(AUC),and retention time(MRT)of the prodrug micelle group increased compared to free RH.The prolonged retention time of RH in cells is beneficial for increasing its toxicity to cells.In summary,the Pluronic SS-RH prodrug micelles prepared in this study have significant redox sensitivity,good stability,and biosafety.In vitro cytotoxicity experiments,cell pharmacokinetic studies,and in vivo pharmacokinetic studies have confirmed that the prodrug micelles can improve the therapeutic effect on tumors and have great potential in tumor treatment.