Rare-Earth Doped NaYF₄ Of Study On The Synthesis Surface Modification And Biological Application

Lanthanide doping up-converted nanoparticles of as host NaYF₄ have the advantages of multicolor emission,large anti-Stokes shift,low cytotoxicity,preeminent light stability,deep penetrating ability of tissue,low background fluorescence,which has excellent application value in biosensor,marking,imaging and treatment.However,The surface hydrophobic properties of up-conversion nanomaterials limit their applications in the medical field.Therefore,in the study,we designed and synthesized large pore mesoporous silica-coated upconversion nanoparticles?UCS?and further loaded dicarboxycisplatin?DSP?and toxic protein ribonuclease a?RNase A?to construct nanopharmaceuticals.The application of UCS-Pt-RNase A in vivo and in vitro nuclear magnetic and upconversion fluorescence imaging and medical anticancer was studied.2%Er,20%Yb:NaYF₄@NaGdF₄ of core-shell structure was synthesized by thermal decomposition at high temperature of method.The nanoparticles are composed of Polycrystalline domain with lattice spacing for 0.52 nm and size for 50 nm.Large pore size mesoporous silica coated upconversion nanoparticles UCS were synthesized by microemulsion method.The results of morphology and performance analysis show that the average pore size of UCS are 80 nm,the average pore size is 3.4 nm,the average pore volume is 1.5 c²/g,and the average specific surface area of 479.8m²/g with the properties of NMR and upconversion fluorescence.The loading efficiency of DSP and RNase A were tested by covalent bonding and electrostatic adsorption on the surface of UCS.The average load efficiency of Pt⁴⁺and RNase A were 2.9%and 15.75%,respectively.Using UCS-Pt-RNase A as drug delivery carrier of drug delivery was realized by endocytosis of cells.Under the synergetic action of drugs,induction of apoptosis of hepatoma by destroying that structure of DNA and RNA.Thus,the growth of tumor cells was inhibited.Furthermore,up-conversion fluorescence imaging of in vivo/in vitro can be realized under 980 nm near-infrared light,and dual-mode imaging can be realized by combining with nuclear magnetic resonance imaging.Finally,the UCS-Pt-RNase A was applied to mouse tumor model in vivo.The integrated treatment and diagnosis system of anti-tumor therapy and dual-mode imaging was realized by drug synergy,and good anti-tumor effect was obtained.It is expected to be used in anti-tumor growth and diagnosis and treatment in medicine.