Preparation And Antitumor Activity Of Triphenylphosphine-based Mitochondrial Targeting Polylactic Acid Nanoparticles Loaded With 7-hydroxyl Coumarin

Objective: Based on the principle of electric charge,lipophilic cations can be attracted to mitochondria through electrostatic action,and accumulate in the mitochondrial matrix,leading to apoptosis.In this study,a carrier material formed by the chemical combination of triphenylphosphine and polylactic acid was used to encapsulate anti-tumor drugs and prepare nanoparticles to study its mitochondrial targeting and anti-tumor effects.Methods: The nanoparticle carrier material triphenylphosphine-polylactic acid(TPP-PLLA)was synthesized by chemical synthesis,and the structure was confirmed by Fourier infrared transform spectrometer,ultraviolet spectrophotometer,1H-NMR spectrum and other instruments.The triphenylphosphine-polylactic acid nanoparticles(7-HC/TPP-PLLA nanoparticles,7-HC/TPP-PLLA NPs)were prepared by the emulsification-solvent evaporation method,and the anti-tumor drug 7-hydroxyl coumarin(7-HC)were encapsulated in the internal water phase.The particle size,encapsulation efficiency,and drug loading of the nanoparticles were used as evaluation indicators.The single factor method was used to investigate the influences of external emulsifier type,external emulsifier concentration,internal emulsifier dosage,carrier material quality,and the volume ratio of organic phase to internal water phase on 7-HC/TPP-PLLA NPs evaluation indicators.So as to determine the optimization range of factors.On this basis,the response surface Box-Behnken method was used to optimize the prescription process,and finally to verify the prescription.The apparent properties of the nanoparticles were characterized by Malvern particle size analyzer,transmission electron microscope,etc.,and the biocompatibility and cell proliferation ability of the nanoparticles were preliminarily evaluated by cell migration experiment,hemolysis experiment,blood biochemical analysis and CCK-8 experiment.The apparent properties of the nanoparticles were characterized by Malvern particle size analyzer,transmission electron microscope,etc.,and the biocompatibility and cell proliferation ability of the nanoparticles were preliminarily evaluated by cell migration experiment,hemolysis experiment,blood biochemical analysis and CCK-8 experiment.Finally,the blank nanoparticles were labeled with fluorescein,and the mitochondrial targeting ability of the new material was studied through confocal cell experiments.Results: The triphenylphosphine-polylactic acid carrier material was successfully prepared,and the optimal formulation and preparation process of7-HC/TPP-PLLA NPs was obtained by response surface screening,that is,the internal emulsifier was 0.2500 g Span 80 and 0.0100 g carrier material,3 m L of organic phase dichloromethane,2.5% SDS aqueous solution as external emulsifier.The average particle size of 7-HC/TPP-PLLA NPs was 64.27±0.012 nm,PDI was0.34±0.006,encapsulation efficiency was(68.24±1.26)%,and drug loading was(15.225±0.115)%.In the stability study,the particle size and Zeta potential did not change significantly.The carrier material had no significant effect on the hemolysis of red blood cells and there was no obvious abnormality in blood biochemical indicators.TPP-PLLA NPs successfully targeted mitochondria,and the IC50 value(2.7705 μM)of 7-HC/TPP-PLLA NPs was significantly lower than that of 7-HC(23.930 μM).Conclusion: The TPP-PLLA carrier material was successfully synthesized,and the 7-HC/TPP-PLLA NPs with smaller particle size,higher encapsulation efficiency and drug loading,and stable storage were obtained.It is helpful for nanoparticles to target mitochondria to exert a better anti-tumor effect.