Construction Of Folic Acid-mediated Superparamagnetic Iron Oxide Nanoparticles Loaded Paclitaxel And Hydroxycamptothecin And Application In Targeting Anti-nasopharyngeal Carcinoma

Objective:1.To optimize the preparation conditions of folic acid ligand-coupled superparamagnetic iron oxide nanoparticles?SPIONs?.2.Addressing the hydrophobicity and non-targeting of paclitaxel.3.To Constructe a folic acid-mediated superparamagnetic iron oxide nanoparticle system of traditional Chinese medicine components?paclitaxel?PTX?and hydroxycamptothecin?HCPT??.4.The dual-targeting effect of the drug delivery system on nasopharyngeal carcinoma cells was initially explored at the cell level,which laid the foundation for the subsequent construction of a multifunctional superparamagnetic nanomedicine delivery system modified by folate ligands.Methods:1.Based on the previous research,using the EDC/NHS method,by designing different solvents?DMSO,DMF and 0.1 M Na HCO₃?to activate folic acid?FA?,a single factor investigation was conducted,combined with characterization indicators such as particle size and potential to further optimize the reaction conditions of folic acid-grafted superparamagnetic iron oxide nanoparticles?FA@PEG/PEI-SPIONs?and determine the optimal conditions for the reaction.2.In order to solve the hydrophobicity of PTX,the structural modification of PTX was carried out using succinic anhydride as a bridge molecule to obtain 2'-succinate paclitaxel?SPTX?.SPTX was loaded on the optimized FA@PEG/PEI-SPIONs to construct a folic acid-mediated PTX superparamagnetic iron oxide nanoparticle system?SPTX@FA@PEG/PEI-SPIONs?.3.HCPT was loaded on FA@PEG/PEI-SPIONs by physical adsorption method to construct a folic acid-mediated HCPT superparamagnetic iron oxide nanoparticle system?HCPT@FA@PEG/PEI-SPIONs?.4.Nasopharyngeal carcinoma cell lines with expressions of folate receptor negative?CNE-1?and positive?HNE-1?were used to investigate the dual targeting of folic acid modified superparamagnetic nanoparticles at the cellular level.Results:1.The prepared FA@PEG/PEI-SPIONs have good water dispersibility and hydrodynamic particle size is less than 180 nm.DMSO,DMF and 0.1M Na HCO₃ was used as the activating solvent,the average particles sizes of FA@PEG/PEI-SPIONs observed in TEM was 13.06±1.98 nm,12.87±2.12nm and 12.22±2.11 nm,respectively,with the folate coupling ratio of 4.5%,4.12%and 4.25%,and the crystal phase of the nanoparticles was composed of both Fe₃O₄ and?-Fe₂O₃.Prussian blue staining showed that FA@PEG/PEI-SPIONs had highly targeted ability to HNE-1?folate receptor positive?FAR+?expression cells?.Final optimization conditions:DMSO plus triethylamine or 0.1 M Na HCO₃ was used as folic acid activation solvent,m_?FA?:m_{?PEG/PEI-SPIONs?}=1:1,Fe concentration of PEG/PEI-SPIONs was 1.2mg/m L,25 C,100 rpm/min magnetic stirring for 24 h.2.The 2'-succinate paclitaxel?SPTX?was successfully loaded on the surface of FA@PEG/PEI-SPIONs.The formed of SPTX@FA@PEG/PEI-SPIONs exhibited water-dispersive monodispersity with high stability,and hydrodynamic size was 184.54±8.95 nm,particles sizes observed in TEM was13.01±1.10 nm,the encapsulation efficiency and drug loading were 82.1%and25.7%,respectively.It releases more than 90%in vitro at p H 5.0,and is highly targeted to HNE-1 cells.3.The HCPT@FA@PEG/PEI-SPIONs are water dispersible and monodisperse with good stability,TEM particles was 13.79±1.67nm.Conclusions:1.The reaction conditions of folic acid grafted SPIONs were optimized.The FA@PEG/PEI-SPIONs system formed had good water dispersibility and high FA grafting rate.2.SPTX@FA@PEG/PEI-SPIONs and HCPT@FA@PEG/PEI-SPIONs nanoparticles with good water dispersibility and dual-targeting were successfully constructed.It also lays a foundation for the construction model of a new nano drug delivery system combining two traditional Chinese medicine active ingredients.