Preparation Of Aptamer-anchored Mesoporous Carbon Nanocarriers And The Application On Drug Targeting Delivery

Mesoporous carbon nanoparticles(MCNs)have attracted significant attention as efficient drug delivery vehicles due to their high specific surface area,tunable pore size,uniform porous structure,stable mechanical strength,favorable chemical inertness and biocompatibility.In this work,mesoporous carbon nanoparticles(MCNs)were synthesized by soft template method.MCNs were first encapsualated with a polyacrylic(PAA)shell,and after doxorubicin(DOX)loading,a polyethyleneimine(PEI)layer was coated to prevent the leakage of DOX.The MUC1 aptamer(Apt)was subsequently anchored onto the surface to provide the ability for specific recognition of cancer cells.We fabricated a multifunctional counterpart with high selectivity and efficiency for cancer therapy.This nanocarrier has been shortly termed as Apt@DP-DOX-MCN.The double polymer shells endowed the drug carrier platform with glutathione(GSH)and pH dual stimuli-responsive capability,and controllable release of the encapsulated drug molecule could be realized from the mesoporous and hollow structure.The anchored MUC1 aptamer facilitates spatiotemporal therapy to improve selectivity towards the objective lesion site and decrease the off-target toxicity.The obtained Apt@DP-DOX-MCN is further characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),Fourier transform infrared spectroscopy(FT-IR)and Raman spectroscopy and so on.The nano-platform is successfully constructed by analysing the structure,morphyology,surface functional groups and so on of Apt@DP-DOX-MCN.The drug loading rate,drug release kinetics,cytotoxicity and targeting property of the drug carrier platform are investigated.A loading ratio of 27.2%is achieved at pH 8.5 with a DOX concentration of 1000 mg mL-1.DOX loaded on DP-DOX-MCN remained stable and only 1.94%of DOX was released within 48 h at pH 7.4.Drug release experiments in vitro show that the drug carrier platform has a pH-and GSH-sensitive release capability and a higher drug release rate(60%).The interaction between the Apt@DP-DOX-MCN and receptor expressed cells has been explored by MTT,laser scanning confocal microscopy imaging and fluorescence detection assay.Cell cytotoxicity,confocal fluorescence microscopyimages and fluorescence spectrophotometry show that the targeted recognition and therapy of human lung adenocarcinoma cancer cells(A549)and breast cancer cells(MCF-7)are successfully achieved.