Preparation Of Red Light-induced PEG Deshielding Nanocarriers For Enhanced Tumor Therapy

Poly?ethylene glycol??PEG?is widely used to modify nano-drugs.It can significantly prolong the circulation time of drugs in the body and can be better gathered in tumor tissues.However,it also reduces the uptake of nano-drugs in tumor cells.To solve the problem,a varivity of PEG deshielding systems have been continuously developed,most of them are based on endogenous stimulus-responsive PEG deshielding,such as the tumor acidity environment and the enzymes specifically expressed at the tumor site.However,the endogenous stimulus-responsive PEG deshielding system is restricted by the tumor heterogeneity.To solve this problem,we desigined a photoinduced PEG deshielding nanoparticle.The nanoparticle is assembled into nanoparticles by nanoprecipitation method,which is composed of reactive oxygen sensitive block polymer m PEG₁₁₃-TK-Ce6-PLA₁₄₀,cell penetrating peptide TAT modified Polylactic acid PLA(TAT-PLA₇₂)and model drug hydrophobic doxorubicin?DOX?.It is called ^PEGNP_Ce6&TAT@DOX.In the vitro experiments of nanoparticles ^PEGNP_Ce6&TAT@DOX,after the nano-medicine was irradiated with a 660nm laser at 0.2W cm^-2 for 30 min,the PEG was about 17%deshielding.Through the characterization of DLS and TEM,the particle size of the nano drug did not change before and after illumination,and its morphology was still regular spherical.The nano-drugs before and after light irradiation were tested in the particle size of DMEM containing 10%FBS,and it was found that the particles did not aggregate,and the nano-drugs before and after light irradiation did not release the drug suddenly.The cell-level studies showed that under the red light of 660 nm,the PEG shell of the nanoparticles ^PEGNP_Ce6&TAT@DOX was removed,the TAT was exposed and the nanoparticles could actively enter under the action of TAT Cells,thereby killing the cells better and enhancing their anti-tumor therapeutic effect...