An up-conversion multi-modal luminescent material, a preparation method and application thereof

Abstract

The application discloses a kind of up and down conversion multimodal luminescent material and its preparation method and application, including the following steps: including the following steps: down conversion material and up conversion material are dispersed in anhydrous ethanol solvent respectively, add dispersing agent and thickening agent, after being dispersed uniformly, prepare uniform stable luminescent material;The down conversion material is: Eu 3+ Complex and / or Tb 3+ Complex and / or Zn 2+ Complex, Eu 3+ , Tb 3+ And Zn 2+ Complex is compounded with polyelectrolyte solution, forms stable polyelectrolyte compounded down conversion luminescent material;The up conversion material is: NaGdF4:Yb, Er nanoparticle, NaGdF4:Yb, Er nanoparticle is modified with water-soluble polymer, forms stable water-soluble NaGdF4:Yb, Er up conversion material.The application has more advantages in the preparation of high security anti-counterfeiting label, information storage and harmful heavy metal ion detection in environment.

Description

TECHNICAL FIELD

[0001] The present application relates to the fields of optics, functional materials and information security, and particularly relates to a kind of up and down conversion multimodal luminescent material and its preparation method and application. 3+ ,Tb 3+ ,Zn 2+ ) and up-conversion nanoparticles (NaGdF4:Yb,Er) to prepare multifunctional fluorescent security ink. The ink realizes orthogonal fluorescence output through dual-mode excitation (UV / NIR), and combines reversible metal ion fluorescence quenching response with high-resolution electrohydrodynamic (EHD) printing technology, and is suitable for dynamic information hiding, environmental heavy metal detection and high-density data storage. BACKGROUND

[0002] In the information age, the importance of information security and storage is increasingly prominent, and traditional information storage and security protection methods face severe challenges. Anti-counterfeiting technology is difficult to resist counterfeiting and unauthorized access due to single-mode detection and predictable encoding strategies. At the same time, in environmental sensing technology, the sensitivity and selectivity of heavy metal ion detection are insufficient, and real-time and accurate monitoring cannot be achieved.

[0003] Luminescent materials show great potential in secure data storage and anti-counterfeiting, and their unique optical properties can achieve multi-level data encoding and secure information retrieval. The response ability to specific stimuli also adds interactivity to the stored information. Existing luminescent materials such as organic dyes, inorganic phosphor powders and semiconductor quantum dots have certain luminescent properties, but cannot meet the requirements of multi-modal excitation, high sensitivity sensing and high-precision printing at the same time. Under natural light, there are visible traces, which are not suitable for various information storage. Therefore, it is of great practical significance to develop a new type of material and system that integrates multi-modal anti-counterfeiting, efficient information storage and accurate environmental sensing. SUMMARY

[0004] The present application aims to provide a new luminescent material for multi-modal anti-counterfeiting and information storage, as well as its preparation method and application, to overcome the shortcomings of the prior art. The luminescent material combines down-conversion and up-conversion luminescent materials to prepare a nanocomposite with dual-mode fluorescence properties. The luminescent material can achieve multi-level data encoding and dynamic information hiding under ultraviolet and near-infrared excitation, realize multi-color luminescence output and orthogonal luminescence characteristics, and has high stability and reversibility. Through electrohydrodynamic (EHD) printing technology, it is not only suitable for information storage and anti-counterfeiting, but also has environmental sensing function, and can detect harmful heavy metal ions.

[0005] The technical solution of the present application is as follows:

[0006] A preparation method of an up-and-down conversion multi-modal luminescent material, comprising the following steps: dispersing a down-conversion material and an up-conversion material in anhydrous ethanol solvent respectively, adding a dispersing agent and a thickening agent, and preparing a uniform and stable luminescent ink after uniform dispersion; the down-conversion material is Eu 3+ complex and / or Tb 3+ complex and / or Zn 2+ complex, the three down-conversion materials can realize red, green and blue multi-color luminescence under ultraviolet (UV) excitation, and have high luminescent efficiency; all of them can combine with ligands to form stable luminescent systems, realize multi-color luminescence, and meet the coding requirements; by compounding Eu 3+ , Tb 3+ and Zn 2+ complexes with a polyelectrolyte solution, a stable polyelectrolyte-compounded down-conversion luminescent material is formed, the biocompatibility and mechanical stability of the material are enhanced, and the material is conducive to the preparation of an environmentally friendly ink formula and a complex pattern; the up-conversion material is NaGdF4:Yb,Er nanoparticles, the up-conversion material emits green light under near-infrared (NIR) excitation, is modified with a water-soluble polymer to form stable water-soluble NaGdF4:Yb,Er up-conversion nanoparticles, and the water dispersibility, stability and viscosity of the nanoparticles are improved, so that the nanoparticles are suitable for an ink system; the luminescent spectra of the down-conversion material and the up-conversion material do not interfere with each other;

[0007] the preparation method of the Eu 3+ complex or the Tb 3+ complex; the preparation of the Eu 3+ or Tb 3+ : the stoichiometric ratio of the first organic ligand to the second organic ligand ranges from 1:1:1 to 1:3:1; the first organic ligand is one of 4-mercaptobenzoic acid (4-MBA), p-chlorobenzoic acid (4-CBA), iminoglutaric acid (IDA), dibenzoylmethane (DBM), 2-thiophenecarbonyl trifluoroacetone (TTA), acetylacetone (AcAc), and 1,2-diaminocyclohexane-1,2-diacetic acid (DCTA); and the second organic ligand is one of 2,2-bipyridine (bpy), 2,2-bipyridine dicarboxylic acid (DPA), 8-hydroxyquinoline (8-Hyd), and 1,10-phenanthroline (Phen).

[0008] the preparation method of the Zn 2+ complex, the preparation of the Zn 2 : the stoichiometric ratio of the organic ligand ranges from 1:1 to 1:3; the organic ligand is one of ethylenediamine (en), ethanolamine (MEA), thiourea (TU), and 2-(2-hydroxyphenyl) benzothiazole (BTZ).

[0009] The preparation method, the polyelectrolyte solution is one of sodium alginate (SA), hyaluronic acid (HA), carboxymethyl cellulose (CMC) and pectin (PGA).

[0010] The preparation method, Eu 3+ / Tb 3+ / Zn 2+ The concentration of the complex: the concentration of the polyelectrolyte solution is in the range of 1:1 to 4:1, which ensures the needs of subsequent preparation of ink.

[0011] The preparation method, Eu 3+ The complex or Tb 3+ The preparation method of the complex is specifically as follows: a first organic ligand solution is added dropwise into an EuCl3·6H2O solution or a TbCl3·6H2O solution, and then the mixture is stirred at room temperature by a magnetic stirrer for 0.5-1 hours; the pH of the reaction solution is adjusted to 6-8 by using dilute ammonia water; a second organic ligand solution is added into the solution, and then the mixture is stirred for 1-2 hours, so as to synthesize Eu 3+ or Tb 3+ complex.

[0012] The preparation method, Zn 2+ The preparation method of the complex is specifically as follows: an organic ligand solution is added dropwise into a ZnCl2 solution, and then the mixture is stirred at room temperature by a magnetic stirrer for 1-2 hours, so as to synthesize Zn 2+ complex; the Eu 3+ , Tb 3+ , Zn 2+ complex is prepared, and then a polyelectrolyte solution is added, and the mixture is stirred at room temperature for 1-2 hours to be compounded, so as to obtain a polyelectrolyte compounded Eu 3+ , Tb 3+ , Zn 2+ down-conversion luminescent material.

[0013] The preparation method, the preparation method of NaGdF4:Yb,Er up-conversion nanoparticles is as follows: GdCl3·6H2O, YbCl3·6H2O and ErCl3·6H2O are mixed with oleic acid and octadecene (ODE) in a container, and then the mixture is stirred and heated to form a clear and uniform solution, and then the mixture is cooled; a methanol solution containing NaOH and NH4F is added, and then the mixture is stirred; the mixture is slowly heated to 110℃ to make methanol and water completely evaporate, and then the mixture is degassed at 110℃ for 20 minutes; the temperature is increased to 300℃, and then the mixture is kept at 300℃ under nitrogen protection for 1.5 hours; after the reaction is completed, the mixture is cooled to room temperature, and then the mixture is washed with ethanol and centrifuged for three times, so as to obtain NaGdF4:Yb,Er nanoparticles

[0014] The preparation method comprises the following steps: preparing NaGdF4:Yb,Er upconversion nanoparticles, and then adding a certain amount of water-soluble polymer for modification, wherein the water-soluble polymer is one of polyethylene glycol (PEG), polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), polyacrylamide (PAM) and polyacrylic acid (PAA), and the modified NaGdF4:Yb,Er nanoparticles enhance the hydrophilicity, and can be better dispersed in the solvent when preparing the luminescent ink, so that the stability and uniformity of the ink are ensured.

[0015] The preparation method comprises the following steps: dispersing agent is one of sodium metaphosphate (SHMP), sodium dodecyl benzene sulfonate (SDBS), polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP), thickening agent is one of gum arabic (GA), gelatin (Gelatin), acrylic resin (AR) and glycerol (GLY), and the volume ratio of the dispersing agent and the thickening agent to the ethanol solvent is adjusted, the proportion of the dispersing agent in the ink mixture is 10%-20%, the proportion of the thickening agent is 30%-40%, and the ink is uniformly obtained after ultrasonic treatment for 0.5-1 hours.

[0016] (1) Multi-modal luminescence interactive regulation

[0017] The luminescent ink is excited by 365nm ultraviolet light and 980nm near-infrared light in a double-mode, multi-modal luminescence interaction is realized by regulating the wavelength, intensity and sequence of the excitation light, RGB three-color fluorescence is emitted under the excitation of 365nm ultraviolet light, green light and red light are emitted under the excitation of 980nm near-infrared light, different fluorescent encoding combinations are realized to meet the needs of multi-modal luminescence interaction for efficient information storage and complex pattern design, and multi-level encoding and dynamic hiding of information are realized.

[0018] (2) Complex pattern preparation

[0019] The luminescent ink is deposited on the surface of a substrate by using electrohydrodynamic (EHD) printing technology, and precise pattern printing with a line width of about 20-150μm is realized. In the printing process, the printing parameters are monitored and regulated in real time to ensure the accuracy and stability of the pattern.

[0020] (3) Information storage and sensing function realization

[0021] The prepared complex pattern is invisible under natural light, and shows independent fluorescent signals under the excitation of UV / NIR double-mode, has a sensitive fluorescent quenching response to drugs and most heavy metal ions, and the quenching process is reversible after the introduction of EDTA, so that the fluorescent recovery and inhibition can be realized for at least three cycles. By selective spraying of heavy metal ion solution and EDTA solution, local fluorescent quenching and recovery are realized, and dynamic control of information display and hiding is realized. Through monitoring and analysis of the fluorescent signals, sensing detection of target substances such as heavy metal ions in the environment is realized.

[0022] In the complex pattern preparation process, various printing modes such as printing, spraying, vertex spinning and electrohydrodynamic printing technology can be used, and the related parameters of printing can be adjusted in real time, for example, if electrohydrodynamic printing technology is used, the voltage is 10-30kV, the flow rate is 0-1 muL / min, the distance between the nozzle and the substrate is 5-10mm, and the stability and consistency of printing are ensured. The line width and size of the point, line and accurate pattern printing are 20-150 mu m. The printed pattern is invisible under natural light, and the encrypted information is read by 250-390nm ultraviolet and 980nm near infrared light double mode excitation.

[0023] Each luminescent ink is injected into the empty needle of the EHD printer, and the pre-designed pattern is printed on the substrate by connecting the EHD printer to the computer, and the photos of the pattern on the printed paper are taken under the 365nm or 980nm excitation lamp.

[0024] The drugs are fluorouracil (5-FU), methotrexate (MTX), paclitaxel (PTX), vincristine (VCR), gefitinib (Gef), pembrolizumab (Pembro), nivolumab (Nivo), niclosamide (NIC), and temozolomide (TMZ).

[0025] The reversible response is realized by spraying a Cu solution with a concentration of 1-200 mu g / mL 2+ The solution triggers fluorescence quenching, and the quenching efficiency is linearly related to the Cu 2+ The fluorescence intensity is attenuated by 15% or less after the EDTA solution is sprayed for 3 cycles.

[0026] By adjusting the proportion of down-conversion and up-conversion material fluorescence intensity, adjusting the proportion of four luminescent materials in the pattern distribution, covering 60-80% of the area of the pattern with a UV light source and covering the remaining area with a NIR light source, changing the excitation order of the excitation light source: first UV then NIR or first NIR then UV or simultaneous excitation of UV and NIR, adjusting the intensity of the excitation light, selectively quenching different types of luminescent materials, the luminescent color, intensity, response performance, etc. of the luminescent pattern can be adjusted, and various fluorescent encoding combinations can be realized to meet the multi-level data encoding and dynamic information hiding requirements.

[0027] The up-conversion and down-conversion multi-modal luminescent material prepared according to the preparation method has the applications in multi-modal anti-counterfeiting label manufacturing, confidential information storage medium, and on-site rapid detection equipment for harmful heavy metal ions and drugs in the environment.

[0028] Compared with the prior art, the beneficial effects of the present application are:

[0029] The unique luminescent ink system constructed by the synergistic effect of the down-conversion complex and the up-conversion nanoparticles can realize multi-color luminescence output under the excitation of ultraviolet light and near-infrared light, realize double-mode independent signal reading, and meet the needs of multi-level data coding and dynamic information hiding. The luminescent ink far exceeds the performance of the existing technology in terms of detection sensitivity, reversibility and anti-interference ability, and can be more accurately used for monitoring of harmful heavy metal ions in the environment. The quenching reversibility after the introduction of EDTA is greater than or equal to 90%, and the fluorescence intensity degradation is small, which exhibits high stability and reversibility, ensuring the reliability and reusability in practical application, supporting dynamic information hiding and rewriting. The luminescent ink is specially prepared for EHD printing technology, and can realize accurate pattern printing with a line width of about 20-50 mu m. The printed pattern is invisible under natural light, and is obvious under excitation light with good continuous printing stability, which improves the level of printing accuracy, pattern concealment and stability of the printing technology, so that the present application has more advantages in making high-security anti-counterfeiting labels, information storage and monitoring of harmful heavy metal ions in the environment. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 Morphology diagram of PAA-NaGdF4:Yb,Er nanoparticles prepared for Example 4; 3+ Morphology diagram of HA-Eu(TTA)3Phen complex of the complex;

[0031] Figure 2 Morphology diagram of PAA-NaGdF4:Yb,Er nanoparticles prepared for Example 4; 3+ Morphology diagram of HA-Tb(AcAc)3Phen complex of the complex;

[0032] Figure 3 Morphology diagram of PAA-NaGdF4:Yb,Er nanoparticles prepared for Example 4; 2+ Morphology diagram of HA-Zn(BTZ) complex of the complex;

[0033] Figure 4 Morphology diagram of PAA-NaGdF4:Yb,Er nanoparticles prepared for Example 4;

[0034] Figure 5 Selectivity of HA-Eu(TTA)3Phen (a), HA-Tb(AcAc)3Phen (b), HA-Zn(BTZ) (c), PAA-NaGdF4:Yb,Er complex (d) to metal ions for Example 5;

[0035] Figure 6 Fluorescence intensity change diagram of HA-Eu(TTA)3Phen, HA-Tb(AcAc)3Phen, HA-Zn(BTZ), PAA-NaGdF4:Yb,Er complex under different concentrations of Cu 2+ for Example 6;

[0036] Figure 7 Example 7 shows the fluorescence intensity changes of the HA-Eu(TTA)3Phen complex under different concentrations of niclosamide;

[0037] Figure 8 Example 8 shows the fluorescence intensity changes of the HA-Tb(AcAc)3Phen complex under different concentrations of temozolomide.

[0038] Figure 9 Images of the downconversion and upconversion luminescent material inks prepared in Example 9 after printing with an EHD printer under excitation light at 365nm or 980nm, with linewidths of 20-50μm.

[0039] Figure 10 The downconversion luminescent material ink and upconversion nanoparticle ink prepared in Example 10 were used for EHD printing. The designed fluorescent patterns were then revealed under simultaneous excitation by ultraviolet and near-infrared light. The patterns were then processed using Cu... 2+ After the quencher is sprayed, the pattern information disappears. After the EDTA revitalizer is sprayed, the pattern information is restored and reappears. This process can be repeated up to 3 times.

[0040] Figure 11 The fluorescent pattern of the downconversion luminescent material ink and upconversion nanoparticle ink used in Example 11, printed using EHD, is then processed by Cu. 2+ Fluorescence intensity changes after 3 cycles of EDTA quenching and reactivation. Detailed Implementation

[0041] The present invention will be described in detail below with reference to specific embodiments.

[0042] Example 1

[0043] EuCl3·6H2O (1.0×10⁻⁶) -3 mol / L), TTA (3.0×10 -1 mol / L) and Phen (1.0×10 -3 Eu(TTA)3Phen was dissolved in ethanol. 1 mL of EuCl3·6H2O and 1 mL of TTA were mixed and stirred at room temperature for 0.5 hours. Then, dilute ammonia was added to adjust the pH to 7-8. 1 mL of Phen was added and stirred at room temperature for 2 hours to obtain the Eu(TTA)3Phen complex. 1 mL of polyelectrolyte HA solution was added and stirred at room temperature for 2 hours to obtain the HA-Eu(TTA)3Phen complex.

[0044] Figure 1The TEM morphology of the prepared HA-Eu(TTA)3Phen complex shows uniform spherical nanoparticle structure with good dispersion stability, and the dispersion in the ink solution is more stable, and problems such as precipitation or agglomeration to block the nozzle do not occur, which is beneficial to ensure the smoothness of the fluorescent ink in the printing process when preparing patterns.

[0045] Example 2

[0046] TbCl3·6H2O (1.0×10 -1 mol / L), AcAc (3.0×10 -1 mol / L) and Phen (1.0×10 -3 mol / L) were dissolved in ethanol, respectively. 1 mL of TbCl3·6H2O and 1 mL of AcAc were mixed, stirred at room temperature for 0.5 hours, then diluted ammonia was added to adjust the pH to 7-8, 1 mL of Phen was added, and stirred at room temperature for 2 hours to obtain Tb(AcAc)3Phen complex. 1 mL of polyelectrolyte HA solution was added, and stirred at room temperature for 2 hours to prepare HA-Tb(AcAc)3Phen complex.

[0047] Figure 2 The morphology of the prepared HA-Tb(AcAc)3Phen complex shows regular spherical nanoparticles with uniform particle size, which can be uniformly distributed in the ink, and the fluorescent properties of Tb 3+ can be fully utilized, the fluorescent intensity is uniformly distributed, and the display effect of the fluorescent ink is improved.

[0048] Example 3

[0049] ZnCl2 (2.0×10 -2 mol / L), BTZ (2.0×10 -2 mol / L) were dissolved in ethanol, respectively. 1 mL of ZnCl2 and 1 mL of BTZ were mixed, stirred at room temperature for 2 hours to obtain Zn(BTZ) complex, and 1 mL of polyelectrolyte HA solution was added, and stirred at room temperature for 2 hours to prepare HA-Zn(BTZ) complex.

[0050] Figure 3 The morphology of the prepared HA-Zn(BTZ) complex shows regular spherical nanoparticles, and the particles are uniformly distributed and dispersed, indicating that the complex has good dispersibility, so that the Zn 2+ complex can exist stably in the ink, ensuring the stability and usability of the fluorescent ink.

[0051] Example 4

[0052] GdCl3-6H2O, 0.2 mmol YbCl3-6H2O and 0.02 mmol ErCl3-6H2O were mixed with 8 mL of oleic acid and 12 mL of octadecene (ODE) in a flask, stirred and heated to 150°C to form a clear and uniform solution, cooled to 50°C; 9 mL of methanol solution containing 2.5 mmol NaOH and 4 mmol NH4F was added, stirred for 30 minutes; slowly heated to 110°C to completely evaporate methanol and water, degassed at 110°C for 20 minutes; heated to 300°C, kept for 1.5 hours under nitrogen protection; after the reaction was completed, cooled to room temperature, washed with ethanol and centrifuged three times to obtain NaGdF4:Yb,Er nanoparticles. The obtained upconversion nanoparticles were redispersed in 10 mL of cyclohexane, and 10 mL of ethanol solution containing 1.58 g of PAA was sequentially added to the flask, stirred at room temperature for 6 hours, after the reaction was completed, the mixed solution was washed with ethanol and deionized water three times and centrifuged, and the product was vacuum dried at 60°C for 10 hours to obtain hydrophilic PAA-NaGdF4:Yb,Er nanoparticles.

[0053] Figure 4 The morphology of the prepared PAA-NaGdF4:Yb,Er nanoparticles was spherical, with regular size and uniform distribution, which could be better dispersed in the solvent when preparing the luminescent ink, ensuring the stability and uniformity of the ink.

[0054] Example 5

[0055] The HA-Eu(TTA)3Phen complex prepared in Example 1, the HA-Tb(AcAc)3Phen complex prepared in Example 2, the HA-Zn(BTZ) complex prepared in Example 3, and the PAA-NaGdF4:Yb,Er nanoparticles prepared in Example 4 were subjected to selective detection of metal ions. A stock solution of metal ions with a concentration of 1M was prepared, including potassium (K), calcium (Ca), magnesium (Mg), nickel (Ni), iron (Fe), and copper (Cu). 1 mL of 1M solution of different drugs was added to the solutions prepared in Examples 1, 2, 3, and 4, respectively, and stirred at a speed of 800 rpm for 0.5 hours at room temperature, and then subjected to fluorescence spectrum test. In all fluorescence spectrum measurements, the excitation wavelength of Eu 3+ was 382 nm, the emission wavelength was 612 nm, the emission slit width was 0.5 nm, the excitation wavelength of Tb 3+ was 334 nm, the emission wavelength was 546 nm, and the emission slit width was 0.5 nm, the excitation wavelength of Zn 2+ was 420 nm, the emission wavelength was 462 nm, and the emission slit width was 1 nm, and the excitation wavelength of PAA-NaGdF4:Yb,Er nanoparticles was 980 nm, the emission wavelength was 544 nm, and the emission slit width was 1 nm.

[0056] Figure 5 The HA-Eu(TTA)3Phen, HA-Tb(AcAc)3Phen, HA-Zn(BTZ), PAA-NaGdF4:Yb,Er complexes showed high selectivity for metal ions compared to other tested metal ions, particularly Cu. 2+ The complex exhibits strong fluorescence quenching properties, indicating that it enhances the fluorescence quenching effect on Cu. 2+ Special selectivity.

[0057] Example 6

[0058] The HA-Eu(TTA)3Phen complex prepared in Example 1, the HA-Tb(AcAc)3Phen complex prepared in Example 2, the HA-Zn(BTZ) complex prepared in Example 3, and the PAA-NaGdF4:Yb,Er nanoparticles prepared in Example 4 were subjected to Cu... 2 + Sensitivity detection was performed by preparing Cu solutions with concentrations ranging from 1 μg / mL to 200 μg / mL. 2+ Solution. Add 1 mL of Cu solutions of different concentrations. 2+ The solution was added to the solutions prepared in Examples 1, 2, 3, and 4, and stirred at room temperature for 0.5 hours. The resulting samples were then subjected to fluorescence spectroscopy testing. 3+ The excitation wavelength is 382 nm, the emission wavelength is 612 nm, the emission slit width is 0.5 nm, and Tb 3+ The excitation wavelength is 334 nm, the emission wavelength is 546 nm, and the emission slit width is 0.5 nm. (Zn) 2+ The excitation wavelength was 420 nm, the emission wavelength was 462 nm, and the emission slit width was 1 nm. For PAA-NaGdF4:Yb,Er nanoparticles, the excitation wavelength was 980 nm, the emission wavelength was 544 nm, and the emission slit width was 1 nm. Figure 6 It can be seen from this that, under a certain Cu 2+ Within the concentration range, as Cu 2+ With increasing concentration, the luminescence intensity of both downconversion and upconversion luminescent solutions significantly decreased, indicating that Cu... 2+ The addition of [a substance] can effectively quench fluorescence.

[0059] Figure 6 To detect different concentrations of Cu 2+ The fluorescence intensity changes of the HA-Eu(TTA)3Phen, HA-Tb(AcAc)3Phen, HA-Zn(BTZ), PAA-NaGdF4:Yb,Er complex are shown in the graph. Within a certain range, with Cu... 2+The fluorescence intensity of the complex decreases with the increase of the concentration of Cu 2+ can effectively quench the fluorescence of the complex.

[0060] Example 7

[0061] The HA-Eu(TTA)3Phen complex prepared in Example 1 was used for sensitive detection of niclosamide, and irinotecan solutions with concentrations from 1 ug / mL to 100 ug / mL were prepared. 1 mL of niclosamide solution with different concentrations was added to the solution prepared in Example 1, and the fluorescence spectrum was tested after stirring at room temperature for 0.5 hours. In all fluorescence spectrum measurements, the excitation wavelength of Eu 3+ was 382 nm, the emission wavelength was 612 nm, and the emission slit width was 0.5 nm, Figure 7 As can be seen from the fluorescence intensity change graph of the HA-Eu(TTA)3Phen complex under different concentrations of niclosamide, the fluorescence intensity of the complex decreases significantly with the increase of the concentration of niclosamide in a certain concentration range, indicating that niclosamide can effectively quench the fluorescence of the complex.

[0062] Figure 7 As can be seen from the fluorescence intensity change graph of the HA-Eu(TTA)3Phen complex under different concentrations of niclosamide, the fluorescence intensity of the complex decreases significantly with the increase of the concentration of niclosamide in a certain concentration range, indicating that niclosamide can effectively quench the fluorescence of the complex.

[0063] Example 8

[0064] The HA-Tb(AcAc)3Phen complex prepared in Example 2 was used for sensitive detection of temozolomide, and temozolomide solutions with concentrations from 1 uM to 200 uM were prepared. 1 mL of temozolomide solution with different concentrations was added to the solution prepared in Example 2, and the fluorescence spectrum was tested after stirring at room temperature for 0.5 hours. In all fluorescence spectrum measurements, the excitation wavelength of Tb 3+ was 334 nm, the emission wavelength was 546 nm, and the emission slit width was 0.5 nm, Figure 8 As can be seen from the fluorescence intensity change graph of the HA-Tb(AcAc)3Phen complex under different concentrations of temozolomide, the fluorescence intensity of the complex decreases significantly with the increase of the concentration of temozolomide in a certain concentration range, indicating that temozolomide can effectively quench the fluorescence of the complex.

[0065] Figure 8 As can be seen from the fluorescence intensity change graph of the HA-Tb(AcAc)3Phen complex under different concentrations of temozolomide, the fluorescence intensity of the complex decreases significantly with the increase of the concentration of temozolomide in a certain concentration range, indicating that temozolomide can effectively quench the fluorescence of the complex.

[0066] Example 9

[0067] 5mL of down-conversion solution, 5mg of up-conversion nanoparticles were placed in the mixed solvent of ethanol, PVP and glycerol respectively, and the total volume was 10mL. In order to obtain the ink with the best viscosity and surface tension, the volume ratio of ethanol, PVP and glycerol was kept at 5:2:3. After the above down-conversion solution and up-conversion nanoparticle solution were mixed uniformly with the mixed solvent, four kinds of fluorescent inks were obtained: HA-Eu(TTA)3Phen, HA-Tb(AcAc)3Phen, HA-Zn(BTZ), PAA-NaGdF4:Yb,Er were used as red, green, blue and green inks respectively. Each solution was directly used as anti-counterfeiting ink. Each luminescent ink was injected into the empty needle of the EHD printer. The EHD printer connected to the computer was used to print the pre-designed pattern on the paper without using fluorescent agent. The voltage was set to 10-30kV, the flow rate was 0.1-1μL / min, the distance between the nozzle and the substrate was 5-10mm, and the precise pattern printing with line width of 20-50μm was realized by EHD printing. The photos of the patterns printed on the paper under the excitation of 365nm or 980nm excitation lamp.

[0068] Figure 9 The patterns of the straight lines of the four luminescent down-conversion and up-conversion luminescent material inks of EHD printing under the irradiation of 365nm or 980nm excitation light were demonstrated. Figure (a) is the red straight line pattern produced by the Eu 3+ complex fluorescent ink, figure (b) is the green straight line pattern produced by the Tb 3+ complex fluorescent ink, figure (c) is the blue straight line pattern produced by the Zn 2+ complex fluorescent ink, and figure (d) is the green straight line pattern produced by the PAA-NaGdF4:Yb,Er fluorescent ink, which shows that the luminescent complex ink emits different colors of fluorescence under UV / NIR excitation light. The printing process is suitable for the ink, and the lines are neat and clear, with uniform line width and spacing, and the line width is 20-50μm.

[0069] Example 10

[0070] The ink was deposited on the surface of the non-fluorescent paper substrate by EHD printing technology, and the two-dimensional code pattern was printed according to the printing parameters described in Example 9, and the encrypted information was read by double-mode excitation. The hidden information was realized by spraying Cu 2+ solution to quench fluorescence, and the fluorescent information was recovered by spraying 0.1M EDTA solution, and the cycle operation was 3 times. The prepared pattern is invisible under natural light, and under the excitation of 365nm ultraviolet light and 980nm near infrared light, Eu 3+ / Tb 3+ / Zn 2+The down-conversion material complexed with HA and the up-conversion material of NaGdF4:Yb,Er nanoparticles with core-shell structure and combined with PAA emit fluorescence respectively. By exciting with light sources with corresponding wavelengths, red, green and blue fluorescence from the down-conversion material under UV excitation and fluorescence from the up-conversion material under NIR excitation can be separately identified and recorded, achieving dual-mode independent signal reading. By adjusting the fluorescence intensity ratio of the down-conversion and up-conversion materials, the intensity of the excitation light, the proportion of the four luminescent materials in the pattern distribution, i.e. UV light source covering 60-80% of the pattern area and NIR light source covering the remaining area, changing the excitation order of the excitation light sources, i.e. UV first and then NIR or NIR first and then UV or simultaneous excitation of UV and NIR, and combining Cu 2+ / drug concentration changes to quench different types of luminescent materials, the introduction of EDTA to revive fluorescence, etc., the pattern realizes a variety of different fluorescence encoding combinations through fluorescence changes, and achieves dynamic information update and hiding to meet the needs of multi-level data encoding and dynamic information hiding.

[0071] Figure 10 The application of the four complexes in EHD printing is demonstrated, and the dual-mode optical properties of the printed patterns are depicted. Figure 10 (a) The pattern prepared by EHD is invisible under natural light, Figure 10 (b) The red, green and blue fluorescence patterns emitted by the three down-conversion materials are clearly visible when excited by UV light, Figure 10 (c) The green fluorescence pattern emitted by the up-conversion under near-infrared light excitation is visible, Figure 10 (d)), as shown in Figure 10 (e), when Cu 2+ solution is sprayed onto the pattern, complete fluorescence quenching occurs in the pattern, and then EDTA is sprayed on the quenched area, and the fluorescence is restored Figure 10 (f)), and then a second spraying of Cu 2+ and EDTA solution can be performed on the basis of the first restored pattern information, and the pattern information is also completely revealed Figure 10 (g)). The reversible nature of fluorescence switching is shown, which can be repeated for three cycles.

[0072] Example 11

[0073] The fluorescent patterns printed by EHD in Example 10 are quenched by Cu 2+ each time, and the samples obtained before and after quenching and revival by EDTA are subjected to fluorescence spectrum testing of HA-Eu(TTA)3Phen, HA-Tb(AcAc)3Phen, HA-Zn(BTZ), PAA-NaGdF4:Yb,Er. The fluorescence intensity decay rate is ≤15% per time.

[0074] Figure 11 are the fluorescence patterns of down-conversion luminescent material ink and up-conversion nanoparticle ink after EHD printing, and Cu 2+ The fluorescence intensity change diagram after EDTA quenching quenching and recycling for 3 times. Figure 11 (a) is HA-Eu(TTA)3Phen, Figure 11 (b) is HA-Tb(AcAc)3Phen, Figure 11 (c) is HA-Zn(BTZ), Figure 11 (d) is PAA-NaGdF4:Yb,Er. Although a slight decrease in fluorescence intensity was observed in consecutive cycles, the integrity of the encoded information was still preserved. This dual-mode excitation mechanism provides a powerful means for multi-layer information encryption and enhanced anti-counterfeiting applications. In addition, the prepared patterns also showed a selective response to Cu 2+ .

[0075] It should be understood that, for those of ordinary skill in the art, improvements or changes can be made according to the above description, and all such improvements and changes shall fall within the protection scope of the appended claims of the present application.

Claims

1. Application of an upconversion multimodal luminescent material in rapid on-site detection of drugs, characterized in that, The drug is niclosamide, and the preparation method of the up-conversion and down-conversion multi-modal luminescent material comprises the following steps: dispersing a down-conversion material and an up-conversion material in anhydrous ethanol solvent respectively, adding a dispersant and a thickening agent, and preparing a uniform and stable luminescent material after uniform dispersion; the down-conversion material is Eu 3+ complex and / or Tb 3+ complex and / or Zn 2+ complex, Eu 3+ , Tb 3+ and Zn 2+ complexes are respectively compounded with a polyelectrolyte solution to form a stable polyelectrolyte-compounded down-conversion luminescent material; the up-conversion material is NaGdF4:Yb, Er nanoparticles, the NaGdF4:Yb, Er nanoparticles are modified with a water-soluble polymer to form a stable water-soluble NaGdF4:Yb, Er up-conversion material; the Eu 3+ , Tb 3+ and Zn 2+ complexes are respectively Eu(TTA)3Phen complex, Tb(AcAc)3Phen complex and Zn(BTZ) complex.

2. Use according to claim 1, characterized in that, The polyelectrolyte solution is one of sodium alginate, hyaluronic acid, carboxymethyl cellulose, pectin. The polyelectrolyte solution is one of sodium alginate, hyaluronic acid, carboxymethyl cellulose, pectin.

Images