Its characteristic lies in: with oil Acid, oleylamine and octadecene as solvents were combined with lithium trifluoroacetate, lutetium trifluoroacetate and rare earth trifluoroacetate in an inert gas Under the protection, the temperature is heated to 100-130℃ and held for a period of time to dissolve the solid reactants; And then it’s added under inert gas protection After the thermal solution was heated to 280-330℃ for a period of time, the shell precursor was injected. After the thermal insulation and curing, the shell precursor was injected again for the thermal insulation and ripening. Core-shell nanoparticles with different shell thickness were synthesized through different injection times. After the reaction, the nanoparticles with core shell structure of oil-soluble rare earth doped lutetium fluoride lithium were obtained by precipitation and washing with acetone at room temperature. Water-soluble core-shell nanoparticles were prepared by the following two methods: (1) The above oil-soluble nanoparticles were mixed with acidic ethanol solution, followed by ultrasonic for a period of time and centrifuged for precipitation. Water-soluble rare earth doped lutetium lithium nanoparticles were obtained by washing them with anaqueous ethanol and water for several times (; 2) will be dispersed in the oil soluble nanoparticles in cyclohexane solution with four fluoboric acid dissolving nitroso methylene chloride solution mixing, stirring reaction after a period of time the centrifugal sedimentation, sediment and will be back scattered in dimethyl formamide, adding suitable amount of ethanolamine phosphate, centrifugal, mixing reaction after a period of time and water and dimethyl formamide washing several times to get water soluble rare earth doped lutetium lithium fluoride nanomaterials.
Technical background
In recent years, rare earth doped on conversion luminescent nanomaterials are used in optical switches, information storage, optoelectronic devices and too Solar batteries and other aspects have shown great application value, the most striking is the recent rise of rare earth doping up Application of light-exchanging nanomaterials in fluorescent biomarkers. Compared with conventional fluorescent labeling materials (such as fluorescent dyes and quantities) In comparison, rARE-earth doped up-converted luminescent nanomaterials have high chemical stability, long fluorescence life and potential biotoxicity Low, and the use of near infrared light source excitation thus has a greater light penetration depth, no biological tissue spontaneous fluorescence and opposite Therefore, it plays an increasingly important role in the field of fluorescence biological detection and biological imaging The role of. At present, the bottleneck problem in the development of up-conversion nanometer fluorescent labeling materials is its low quantum yield. Raise up conversion glow Efficiency and preparation of water-soluble nanocrystals with good luminescence properties are the prerequisites for the application of these materials in fluorescent biomarkers. In the reported material system, fluoride has high chemical stability and low phonon energy (300-500cm) It is a kind of ideal rare earth doped matrix material. At present, researches on rare earth doped fluoride mainly focus on yttrium fluoride Sodium (NaYF4) Studies on lutetium fluoride (LiLuF4), gadolinium fluoride sodium (NaGdF4) or yttrium fluoride lithium (LiYF4), etc In little.
