Near-infrared Responsive Functional Nanomaterials Fabrication And Major Disease Analysis

In this paper,based on the effective synthesis of near-infrared light response multi-functional nanomaterials,we built a self-assembled heterodimer including a metal organic framework loaded with near-infrared response fluorescent nanomaterial and antitumor drugs and plasmonic gold nanorods.We also tested the sustained release process of antitumor medicine loaded in dimer under different pH conditions,and explored multimodal imaging of the dimer nanostructure in vivo.The tumor was successfully removal through chemical and thermal synergistic treatment.In addition,we also fabricated near infrared response chiral iron copper selenide nanomaterials and demonstrated the affinity between different chiral nanoparticles and beta amyloid protein.The mechanism of light-triggered fibril protein dissociation was proved.And then,realizing diagnosis and treatment of neurodegenerative diseases in vivo.First,heterodimers of the zeolitic imidazolate framework（ZIF-8）and gold nanorods（AuNRs）were designed and synthesized through electrostatic interaction.And near infrared response Ag₂S,Ag₂Se,up-conversion fluorescent nanoparticles（UCNP）and doxorubicin hydrochloride（DOX）were loaded into the ZIF-8 during the process of metal organic framework fabrication.Second,the acidic environment of tumor cells was simulated in vitro.When the p H was about 6,the dimer could control release of fluorescent nanoparticles and anti-tumor drugs in the ZIF-8.The constructed near-infrared light-responsive dimer can achieve near infrared II region fluorescence imaging with Ag₂S and Ag₂Se quantum dots,fluorescence imaging of upconversion nanoparticles,photoacoustic imaging and computed tomography（CT）imaging in the intracellular or in vivo.At the same time,depending on treatment of anti-tumor drugs and the thermal effect of gold nanorods,tumor cells were clearance under the combination of chemical and photothermal treatment,which effectively reduced the dosage of anti-tumor drugs and the irradiation intensity that alleviate the toxic and side effects on normal tissues.Third,chiral L/D-Fe_xCu_ySe nanoparticles（L/D-NPs）were firstly fabricated that showed three characteristic peaks at 435,515,and 780 nm（in the range of 400-1,000 nm）on circular dichroism（CD）spectra.The N₂ adsorption-desorption isotherm proved that the prepared nanoparticles were porous and have large specific surface area which facilitated their photocatalytic performance.Fourth,Studies have shown that chiral L/D-NPs interfered with the self-assembly of Aβ42 monomers and triggered the Aβ42 fibrils in dense structures to become looser monomers under 808 nm near-infrared（NIR）illumination.Especially,D-Fe_xCu_ySeNPs had a much higher affinity for Aβ42 fibrils than L-Fe_xCu_ySeNPs.The affinity constant of D-NPs can reach to 2.67×105.In addition,the result of electron spin resonance demonstrated the singlet oxygen and hydroxyl free radical production leading to the fibril dissociation.Fifth,based on the chiral iron copper selenide good biocompatibility and chemical stability,the prepared chiral nanomaterilas effectively removed the fibril adhesion on MN9D cells membrane and reduced the toxicity to the neuron cells under near-infrared light irridiation.In vivo experiments showed that D-Fex_Cu_ySeNPs provided efficient protection against the neuronal damage induced by the deposition of Aβ42 and alleviated the symptoms in a mouse model of AD,leading to the recovery of cognitive competence.