Synthesis Of NaYF₄:Yb,Tm Nanoparticles Doped With Non Rare Earth Ions And Their Application In The Determination Of Tartrazine

Rare earth upconversion luminescence materials based on NaYF4 have several advantages such as low auto luminescence background,high chemical stability,high resistance to photobleaching,low toxicity and good biocompatibility,so they have been extensively applied in biomolecular detection,biological imaging and photodynamic therapy and so on.In recent years,in order to improve the sensitivity of upconverting nanoparticles as an optical probe for analysis and determination,improvement the luminescence intensity of the nanoparticles is a problem that many researchers pay much attention.Based on the above research background,the effects of non rare earth ions doping on the luminescence properties of NaYF4:Yb,Tm nanoparticles were systematically studied,and their application of the nanoparticles was explored.The NaYF4:Yb,Tm nanoparticles doped with non rare earth ions were synthesized by solvothermal method and the effects of the type and concentration of doped ions on the luminescenec properties of NaYF4:Yb,Tm nanoparticles were investigated.The upconversion luminescence of the synthesized nanoparticles was enhanced when doped with appropriate concentration of Al3+,Pb2+,Sn2+,Bi3+,Ba2+,Sr2+,Ca2+,Mg2+,Mn2+and Zn2+ions,respectively.Wherein,when the doping concentration of Al3+was 0.15,the luminescence intensity of the prepared nanoparticles increased mostly,and the luminescence intensity was 15.8 times that of the undoped.When doped with Fe3+,Fe2+,Ni2+ and Cu2+,the luminescence intensity of the prepared nanoparticles decreased.XRD experiments showed that Al3+,Pb2+,Ba2+and Mn2+doped into crystals could induced NaYF4 transition from cubic to hexagonal phase and the crystal phase transition is an important reason for the enhancement emission intensity.The synthesis conditions for prepareing NaYF4:Yb,Tm,Al nanoparticles were optimized based on the luminescence intensity.The nanoparticles were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM)and infrared spectroscopy(IR).The results showed that the nanoparticles were hexagonal phase with high crystallinity,and the nanoparticles were spherical with the size of about 20 nm.In addition,the nanoparticles were coated with polyethylenimine on the surface.The luminescence resonance energy transfer system between NaYF4:Yb,Tm,Al nanoparticles and tartrazine was established by the electrostatic interaction.Based on the resonance energy transfer system,the quantitative determination of tartrazine in food was achieved.The linear range of the method is 1.07×10-4?3.21×10-2 g·L-1 with a detection limit of 6×10-5 g·L-1.This Method was used to detect Tartrazine in candies and alcoholic beverages,and recoveries were 98.4%?107%and 97.8%?106%,respectively.The results proved that the method was accurate and reliable.