Organic/Inorganic Hybrid Nanocarriers With Photothermal Properties

Organic/Inorganic hybrid nanocarriers are very important in the preparation of multifunctional nanocarriers in fabricating gene therapy,drug therapy,photodynamic therapy and other functional theranostics to integrate therapeutic functions with real-time imaging.Photothermal therapy is widely used in cancer therapy because of its lower cost and less side effects.In recent years,inorganic photothermal agents such as Au nanorods(Au NRs),copper sulfide(CuS)and bismuth selenide(Bi2Se3)nanopaticles which have strong absorption in the near-infrared region,draw considerable attention of many researchers for photothermal therapy(PTT)of cancer.Herein,we developed a simple and efficient method to synthesize PGEA/ASC nanohybrids with controlled morphology and monodispersity for combined photothermal-gene therapy of cancer.Meanwhile,Au and CuS could be used for photoacoustic(PA)and computer tomography(CT)imaging which could realize dual modal imaging-guided therapy of cancer.First,degradable silica(SiO2)was coated on the surface of gold nanorods.Then,a kind of functional metal-phenolic network(MPN)film was formed simply by mixing tannin(TA)and copper(?)ions in the present of AuNRs@SiO2 nanoparticles.Subsequently,the thioacetamide(TAA)solution was added and reacted with copper(?)ions to form copper sulfide.In order to prepare AuNR-based gene carriers,cationic polymer ethanolamine(EA)-functionalized poly(glycidyl methacrylate)(PGEA)was grafted onto the CuS surface.The obtained PGEA modified ASC nanohybrids can be used for combined photothermal-gene therapy(PTT/GT)of cancer,attributable to the enhanced synergistic photothermal effect of Au and CuS and the electrostatic interaction of PGEA and gene.Compared with the first NIR(NIR-?)window light(750-900 nm),the light in the second NIR(NIR-?)window(1000-1400 nm)have greater penetration depth and less damage to the organism.Furthermore,the polymer PGEA can improve the dispersion of ASC nanoparticles.The SiO2 layer of ASC-PGEA can degrade,which could help pDNA release and promote the elimination of gene carriers from the body.In addition,we investigated a simple solvothermal method to synthesize a new morphology of Bi2Se3 nanosheets.Bi2Se3 is a new type of photothermal therapeutic agent and has a good application prospects in imaging and radiation therapy.We obtain a Janus nanostructure of dextran and Bi2Se3 by a simple nonsolvent-aided counterion complexation method.The resultant Janus Bi2Se3-dextran nanohybirds render their subsequent faicle functionalization with low-toxicity cationic gene vectors(PGEA),which could achieve imaging-guided treatment by integrating CT and PA imaging,PTT and radiotherapy(RT).Then combined with our previously synthesized low-toxicity cationic polymer to synthesize multi-functional gene carrier to realized daul modal CT/PA imaging guided PTT/RT.The currenet nanohybirds provide new avenue for the construction of versatile theranostic platform with photothermal properties.