A method for preparing high quantum yield core-shell-shell structure self-assembled near-infrared nanoparticles

Abstract

The application provides a preparation method of high-quantum-yield core-shell-shell self-assembled near-infrared nanoparticles, characterized by comprising the following steps: dissolving an amphiphilic polymer, near-infrared quantum dots modified with oleic acid and an AIE dye in chloroform respectively, then mixing the three together, adding sodium dodecyl sulfate for emulsification, adding ultrapure water after the emulsification is completed, and removing chloroform by rotary evaporation, and obtaining the self-assembled near-infrared nanoparticles after centrifugation and alkali water treatment. The near-infrared quantum dots modified with oleic acid and the AIE dye are encapsulated by using the amphiphilic polymer poly, and the self-assembled near-infrared nanoparticles with a core-shell-shell three-layer structure are successfully constructed.

Description

Technical Field

[0001] This invention belongs to the field of near-infrared fluorescent nanomaterials technology, specifically relating to a method for preparing high quantum yield core-shell-shell structured self-assembled near-infrared nanoparticles. Background Technology

[0002] Near-infrared (NIR) light has wide applications in science and industry, particularly in biomedical imaging, therapy, and substance detection. In biomedical imaging, because NIR light can penetrate deep into tissues and is relatively harmless, it is widely used in non-invasive imaging techniques such as fluorescence imaging, which helps monitor the functional state of cells and tissues, as well as for early disease diagnosis. In therapy, NIR light is often used in photodynamic and photothermal therapy to treat cancer and other diseases. In the field of substance detection, NIR technology is used for chemical composition analysis, such as food safety testing and environmental monitoring. An increasing number of near-infrared fluorescent nanoparticles are being developed, including quantum dots, organic dyes, aggregation-induced emission dyes, upconversion luminescent nanomaterials, metal particles, and polymers. However, the limited quantum conversion efficiency, low biocompatibility, and weak chemical and photostable stability of these nanoparticles restrict their development in the medical field.

[0003] To address the shortcomings of near-infrared nanomaterials, various strategies have been employed, primarily including surface modification and polymer encapsulation. Surface modification typically involves attaching biocompatible molecules, such as polyethylene glycol (PEG), silane compounds, or biomolecules, to the surface of nanoparticles to improve biocompatibility, reduce toxicity, enhance stability, and prevent nonspecific adsorption. Polymer encapsulation, using polymers such as PVP and PMAO, also helps improve the stability and biocompatibility of nanomaterials and can be used to control drug release.

[0004] While surface modification can improve the biocompatibility and stability of nanomaterials, this process may adversely affect the intrinsic properties of nanoparticles. First, surface modification can alter the size, shape, and surface charge of nanoparticles, which can affect their optical and electronic properties, thereby influencing their fluorescence properties and quantum yield. Furthermore, the selection of surface modification materials and the degree of modification require precise control to avoid performance degradation due to over-modification.

[0005] Polymer encapsulation, while an effective method for improving the biocompatibility and stability of nanoparticles, can lead to nanoparticle aggregation in certain situations, resulting in fluorescence quenching. This is because when nanoparticles are too close together in a polymer matrix, energy transfer or electronic coupling may occur, leading to a decrease in fluorescence intensity. Therefore, polymer encapsulation strategies need to be carefully designed to ensure that nanoparticles remain properly dispersed within the encapsulation material, thereby maintaining their fluorescence properties.

[0006] The unique characteristic of aggregation-induced emission (AIE) dyes is that they do not undergo fluorescence quenching when aggregated; instead, aggregation enhances fluorescence efficiency. This is because the movement of AIE dye molecules is restricted in the aggregated state, reducing the chance of non-radiative energy dissipation. Simultaneously, the increased π-π bond stacking efficiency leads to more efficient electron resonant transport, thereby enhancing fluorescence emission. However, existing encapsulation methods such as polymer encapsulation, template-based encapsulation, microemulsion technology, sol-gel methods, and electrospinning often result in uneven distribution of AIE molecules, leading to unsatisfactory aggregation and low fluorescence quantum efficiency. Summary of the Invention

[0007] To address the problems encountered in existing technologies where individually encapsulating high-quantum-yield quantum dots to increase stability and biocompatibility often results in fluorescence quenching, and where individually encapsulating aggregation-induced emission (AIE) dyes struggles to achieve high aggregation effects, leading to unsatisfactory quantum efficiency, this invention provides a method for preparing high-quantum-yield core-shell-shell self-assembled near-infrared nanoparticles. By simultaneously encapsulating near-infrared quantum dots with oleic acid surface modification and AIE dyes using an amphiphilic polymer, self-assembled near-infrared nanoparticles with a core-shell-shell three-layer structure were successfully constructed. This structure not only significantly improves quantum yield but also optimizes thermodynamic, optical, and colloidal stability.

[0008] The technical problem solved by this invention is achieved by the following technical solution:

[0009] The purpose of this invention is to provide a method for preparing high quantum yield core-shell-shell self-assembled near-infrared nanoparticles, comprising: dissolving an amphiphilic polymer, near-infrared quantum dots with oleic acid surface modification, and AIE dye in chloroform respectively; then mixing the three together evenly; adding sodium dodecyl sulfate for emulsification; after emulsification, adding ultrapure water for rotary evaporation to remove chloroform; and obtaining self-assembled near-infrared nanoparticles after centrifugation and alkaline water treatment; wherein the near-infrared nanoparticles have AIE as the nanoparticle core, near-infrared quantum dots as the inner shell, and an outer shell in which the amphiphilic polymer and sodium dodecyl sulfate are uniformly distributed.

[0010] Furthermore, the near-infrared quantum dots with oleic acid modified on the surface have the same emission wavelength as the AIE dye.

[0011] Furthermore, the near-infrared quantum dots are selected from PbS, PbSe, Ag2S, Ag2Se, CdTe, or CdS quantum dots.

[0012] Furthermore, the mass ratio of the oleic acid-modified near-infrared quantum dots to the AIE dye is 6–12:0.25–2. Preferably, the mass ratio of the oleic acid-modified near-infrared quantum dots to the AIE dye is 9:1.5.

[0013] Furthermore, the mass ratio of the amphiphilic polymer to the oleic acid-modified near-infrared quantum dots is 5:6 to 12. Preferably, the mass ratio of the amphiphilic polymer to the oleic acid-modified near-infrared quantum dots is 5:9.

[0014] Furthermore, a method for preparing high quantum yield core-shell-shell self-assembled near-infrared nanoparticles includes: dissolving 5 mg of an amphiphilic polymer in chloroform, dissolving 6–12 mg of near-infrared quantum dots with oleic acid surface-modified in chloroform, and dissolving 0.25–2 mg of AIE dye in 1 mL of chloroform. After thoroughly mixing the three, 300 μL of 0.5 mg / mL sodium dodecyl sulfate is added for emulsification. After emulsification, 3 mL of ultrapure water is added, and the mixture is rotary evaporated until no bubbles emerge to remove the chloroform. The mixture is then centrifuged at 12,000 rpm for 15 min. The precipitate is treated with sodium hydroxide alkaline solution at pH = 10 for 12 hours, centrifuged to remove the alkaline solution, and then stored in pure water at 4 °C.

[0015] Furthermore, the preparation method of the near-infrared quantum dots with oleic acid modified on the surface is as follows: ODE and OA are added to the cationic compound, the mixture is heated after vacuuming, and after the solid dissolves into a transparent liquid, the mixture is cooled under nitrogen protection; an anionic precursor solution is added to react, acetone is added, the upper liquid is removed after centrifugation, and then the mixture is washed with chloroform for later use.

[0016] Furthermore, the cationic compound is selected from PbO, PbAc, AgAc, CdO, or CdAc.

[0017] Furthermore, the anionic precursor is selected from (TMS)2Se / ODE, (TMS)2S / ODE, or TOP-Te.

[0018] Furthermore, the amphiphilic polymer is selected from PMAO or DSPE-PEG.

[0019] Furthermore, the AIE dye is selected from TPEO-BBT dyes.

[0020] Furthermore, the preparation method of PbS quantum dots with oleic acid surface modification is as follows: ODE and OA are added to PbO, vacuum is drawn and the temperature is raised. After the solid dissolves into a transparent liquid, the temperature is lowered under nitrogen protection. Then, (TMS)2S / ODE precursor solution is added and reacted. After adding acetone and centrifuging, the upper liquid is removed and then washed with chloroform for later use.

[0021] Furthermore, the preparation method of the (TMS)2S / ODE precursor solution is to add (TMS)2S solution to ODE, evacuate under stirring, and keep it under nitrogen protection for later use.

[0022] Furthermore, the obtained self-assembled near-infrared nanoparticles were preserved by adding a solvent, which was one of ultrapure water, buffer solution, or biological sample.

[0023] Furthermore, the alkaline solution is selected from sodium hydroxide solution, potassium hydroxide solution, sodium bicarbonate solution or ammonia water, and the pH value of the product after alkaline treatment is 10.

[0024] Furthermore, the near-infrared nanoparticles have a particle size of 150-350 nm. Preferably, the near-infrared nanoparticles have a particle size of 200-230 nm.

[0025] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0026] This invention forms a composite core-shell-shell three-layer near-infrared nanoparticle that effectively combines the high quantum yield of quantum dots with the aggregation-induced emission (AIE) properties of AIE dyes. It simultaneously encapsulates oleic acid-modified near-infrared quantum dots and AIE dyes using amphiphilic polymers such as polymaleic anhydride-1-octadecene (PMAO) or polyethylene glycol-phospholipid (DSPE-PEG), thereby improving fluorescence intensity. In this invention, high-yield near-infrared quantum dots and AIE dyes with the same emission wavelength are co-encapsulated in a self-assembled nanosphere to achieve synergistic luminescence, which not only improves the overall intensity and efficiency of fluorescence but also ensures the consistency of spectral characteristics.

[0027] This invention utilizes near-infrared quantum dots as the framework within the spheres, ensuring a consistent particle size distribution and good dispersibility, further confining AIE dyes and thus enhancing their aggregation effect. This structure not only enhances the fluorescence efficiency of AIE dyes, but the oleic acid modified on the quantum dot surface also further restricts the movement of AIE molecules, significantly enhancing fluorescence. This is crucial for improving the optical properties and stability of nanoparticles, giving them potential advantages in various high-precision applications.

[0028] This invention ensures particle dispersibility while precisely adjusting the specific mass and ratio of near-infrared quantum dots and AIE dyes, thereby improving fluorescence amplification, maximizing fluorescence signal intensity and stability, and enhancing the accuracy and reliability of fluorescence imaging.

[0029] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0030] Figure 1 This is a flowchart illustrating the preparation method of a high quantum yield core-shell-shell structured self-assembled near-infrared nanoparticle according to the present invention.

[0031] Figure 2 This is an electron microscope image of Example 3 in the preparation method of high quantum yield core-shell-shell structured self-assembled near-infrared nanoparticles of the present invention.

[0032] Figure 3 The fluorescence and absorption spectra of Example 3 in the preparation method of high quantum yield core-shell-shell self-assembled near-infrared nanoparticles of the present invention are shown.

[0033] Figure 4 The images shown are electron microscope images and fluorescence intensity comparison diagrams of Example 4 in the preparation method of high quantum yield core-shell-shell structure self-assembled near-infrared nanoparticles of the present invention, as well as fluorescence intensity comparison diagrams of Comparative Examples 1 and 2 with Example 1.

[0034] Figure 5 The images show the fluorescence spectra, absorption spectra, particle size, and zeta potential distributions of various embodiments and comparative examples in the preparation method of high quantum yield core-shell-shell self-assembled near-infrared nanoparticles of the present invention.

[0035] Figure 6 This is a stability test diagram in the preparation method of high quantum yield core-shell-shell structured self-assembled near-infrared nanoparticles according to the present invention. Detailed Implementation

[0036] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the following embodiments are merely illustrative and explanatory of the present invention and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention.

[0037] In addition, unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be obtained by purchasing them from the market or prepared by existing methods.

[0038] Emulsification was performed using a 960W cell disruption instrument. The parameters during ultrasound operation were: total power 960W 10%, ultrasound time 2min, 9.9 on, 5s off.

[0039] Example 1:

[0040] A method for preparing high quantum yield core-shell-shell self-assembled near-infrared nanoparticles, comprising:

[0041] (1) Preparation of S precursor (TMS) 2S / ODE

[0042] Transfer 25 mL of LODE into a 50 mL single-necked flask, add 1 mL of (TMS)2S solution, and vacuum for 2 hours with stirring. Store under nitrogen protection for later use.

[0043] (2) Preparation of near-infrared PbS-OA quantum dots

[0044] Weigh 0.446 g PbO into a 100 mL three-necked flask, add 20 mL ODE and 1.5 mL OA. Vacuum at room temperature for 5 min, then heat to 120 °C and vacuum for 1 h until the solid dissolves and the solution becomes clear and transparent. After three evacuations, cool to the set reaction temperature of 80 °C under nitrogen protection and hold for 10 min. Quickly inject 5.2 mL of the above (TMS)2S / ODE precursor solution and maintain the injection temperature for another 2 min. Then remove the heat source and rapidly cool to room temperature in an ice-water bath. Add 10 mL acetone, centrifuge at 13500 rpm for 15 min, discard the supernatant, sonicate the lower precipitate in 10 mL chloroform, wash, add acetone to settle, and centrifuge again at 13500 rpm for 15 min. Repeat the above washing operation, disperse the purified nanoparticles in 4 mL chloroform, and store at 4 °C for later use.

[0045] (3) AIE@PbS@PMAO self-assembly

[0046] Weigh out 5 mg PMAO and dissolve it in 50 μL chloroform, 10 mg PbS-OA quantum dots (emission peak 830 nm) and 1.5 mg TPEO-BBT dye (emission peak 830 nm) and dissolve them in 25 μL chloroform. After thoroughly mixing the three, add 300 μL of 0.5 mg / mL sodium dodecyl sulfate and perform crude emulsification. After emulsification, add 3 mL of ultrapure water and rotary evaporate until no more bubbles emerge (30 min). Remove the chloroform, centrifuge at 12000 rpm for 15 min, and the precipitate will have a pH of 9. Add sodium hydroxide solution with a pH of 10 and treat for 12 hours. Centrifuge to remove the alkaline solution, add ultrapure water and store at 4 °C.

[0047] Example 2:

[0048] A method for preparing high quantum yield core-shell-shell self-assembled near-infrared nanoparticles, comprising:

[0049] (1) Preparation of S precursor (TMS)2Se / ODE

[0050] Transfer 25 mL of ODE to a 50 mL single-necked flask, add 1 mL of (TMS)2Se solution, and evacuate under vacuum for 2 hours with stirring. Store under nitrogen protection for later use.

[0051] (2) Preparation of near-infrared PbSe-OA quantum dots

[0052] Weigh 0.446 g PbO into a 100 mL three-necked flask, add 20 mL ODE and 1.5 mL OA. Vacuum at room temperature for 5 min, then heat to 120 °C and vacuum for 1 h until the solid dissolves and the solution becomes clear and transparent. After three gas exchanges, cool to the set reaction temperature of 80 °C under nitrogen protection and hold for 10 min. Quickly inject 5.2 mL of the above (TMS)₂Se / ODE precursor solution and maintain the injection temperature for another 2 min. Then remove the heat source and rapidly cool to room temperature in an ice-water bath. Add 10 mL acetone, centrifuge at 13500 rpm for 15 min, discard the supernatant, sonicate the lower precipitate in 10 mL chloroform, wash, add acetone to settle, and centrifuge again at 13500 rpm for 15 min. Repeat the above washing operation, disperse the purified nanoparticles in 4 mL chloroform, and store at 4 °C for later use.

[0053] (3) AIE@PbSe@DSPE-PEG self-assembly

[0054] Weigh out 5 mg of DSPE-PEG and dissolve it in 50 μL of chloroform, 8 mg of PbSe-OA quantum dots (emission peak 830 nm) and 1 mg of TPEO-BBT dye (emission peak 830 nm) and dissolve them in 25 μL of chloroform. After thoroughly mixing the three, add 300 μL of 0.5 mg / mL sodium dodecyl sulfate and perform crude emulsification. After emulsification, add 3 mL of ultrapure water and rotary evaporate until no more bubbles emerge to remove the chloroform. Centrifuge at 12,000 rpm for 15 min, add sodium hydroxide solution (pH=10) and treat for 12 hours. Centrifuge to remove the alkaline solution, add ultrapure water and store at 4 °C.

[0055] Example 3:

[0056] Unlike Example 1, the amount of PbS-OA quantum dots added in step (3) was 6 mg, 9 mg, and 12 mg, respectively. See Appendix Figure 2 Nanoparticles obtained with three different concentrations were observed using transmission electron microscopy. It was found that as the amount of PbS-OA quantum dots added increased, the color of the nanoparticles deepened, and the particle size gradually increased. However, when the amount of PbS-OA quantum dots added was 12 mg, the particle size uniformity was slightly poor. (See appendix) Figure 3The fluorescence intensity and absorbance of nanoparticles obtained with three different PbS-OA quantum dot contents were measured. It can be seen that the fluorescence intensity gradually increases with the increase of PbS-OA quantum dot content. The optimal amount of PbS-OA quantum dots was 9 mg.

[0057] Example 4:

[0058] Unlike Example 1, the amounts of AIE added in step (3) were 0.25 mg, 0.5 mg, 1.0 mg, 1.5 mg, and 2.0 mg, respectively. See Appendix Figure 4 Electron microscopy and fluorescence emission spectroscopy were performed on nanoparticles with different addition amounts. It can be seen that as the AIE addition amount increases, the particle size of the nanoparticles does not change much, but the fluorescence intensity is significantly enhanced. Compared with the addition amount of 2.0 mg, the fluorescence intensity is not significantly enhanced.

[0059] Comparative Example 1:

[0060] Unlike Example 1, step (3) involves PbS@PMAO self-assembly, prepared as follows:

[0061] Weigh 5 mg PMAO and dissolve it in 50 μL chloroform. Dissolve 9 mg PbS-OA quantum dots (emission peak 830 nm) in 25 μL chloroform. After mixing the two thoroughly, add 300 μL of 0.5 mg / mL sodium dodecyl sulfate for crude emulsification. After emulsification, add 3 mL of ultrapure water and rotary evaporate until no more bubbles emerge (30 min). Remove the chloroform, centrifuge at 12000 rpm for 15 min, and the precipitate is at pH=9. Add sodium hydroxide alkaline water at pH=10 and treat for 12 hours. Centrifuge to remove the alkaline water, add ultrapure water and store at 4 °C.

[0062] Comparative Example 2:

[0063] The preparation method of AIE@PMAO nanoparticles includes the following steps:

[0064] Weigh 5 mg PMAO and dissolve it in 50 μL chloroform. Dissolve 1.5 mg TPEO-BBT dye (emission peak 830 nm) in 25 μL chloroform. Mix the two thoroughly and add 300 μL of 0.5 mg / mL sodium dodecyl sulfate for crude emulsification. After emulsification, add 3 mL of ultrapure water and rotary evaporate until no more bubbles emerge (30 min). Remove the chloroform, centrifuge at 12000 rpm for 15 min, and the precipitate is at pH 9. Add sodium hydroxide alkaline solution at pH 10 and treat for 12 hours. Centrifuge to remove the alkaline solution, add ultrapure water and store at 4 °C.

[0065] Experimental Example 1:

[0066] See appendix Figure 4The left-hand figure shows electron microscopy and fluorescence emission spectroscopy observations of the PMAO-coated PbS quantum dots and AIE dye nanoparticles obtained in Example 1 of this invention, the PMAO-coated PbS quantum dots nanoparticles obtained in Comparative Example 1, and the PMAO-coated AIE dye nanoparticles obtained in Comparative Example 2. It can be seen that compared to nanoparticles coated with PbS quantum dots or AIE dye alone, the present invention, by simultaneously coating PbS quantum dots and AIE dye, forms a core-shell structure, and the particle size is not significantly increased compared to nanoparticles coated with PbS quantum dots alone; however, the fluorescence intensity increases exponentially. See Appendix. Figure 5 Figures d), e), and f show the XRD, XPS, and near-infrared spectra of the three nanoparticles, respectively. It can be seen that the AIE@PbS@PMAO nanoparticles of this invention have been successfully self-assembled.

[0067] Experimental Example 2:

[0068] The fluorescence spectra, particle size, and zeta potential distribution of nanoparticles with different amounts of AIE added in Example 4 of this invention and nanoparticles individually coated with AIE dye were respectively detected. See Appendix. Figure 5 Figures a), b), and c show that changes in the amount added do not affect the wavelength, but do affect the intensity of absorbance; the particle size and zeta potential distribution exhibit good consistency.

[0069] Experimental Example 3:

[0070] See appendix Figure 6 Nanoparticles obtained by replacing the AIE dye in Example 1 with a conventional ICG near-infrared dye (emission peak 815 nm) and the nanoparticles in Example 1 were subjected to laser irradiation for 1 hour or stored in an oven at 45°C for one week, respectively, and their fluorescence decay efficiency was measured. It can be seen that replacing the conventional ICG dye with AIE dye resulted in lower fluorescence decay efficiency and better stability.

[0071] The AIE@PbS@PMAO obtained in Example 1 were stored in ultrapure water, buffer solution, and biological samples, respectively. After adjusting the pH value to 5, 6, 7, 8, and 9, the fluorescence efficiency, particle size, and zeta potential of the nanoparticles after one week of storage were compared. It can be seen that the storage conditions have little effect on the particles, and the obtained AIE@PbS@PMAO near-infrared nanoparticles have good stability.

[0072] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0073] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A method for preparing high quantum yield core-shell-shell self-assembled near-infrared nanoparticles, characterized in that, include: An amphiphilic polymer, oleic acid-modified near-infrared quantum dots, and an AIE dye were dissolved in chloroform. The mass ratio of the oleic acid-modified near-infrared quantum dots to the AIE dye was 6-12:0.25-2, and the mass ratio of the amphiphilic polymer to the oleic acid-modified near-infrared quantum dots was 5:6-12. The three were then mixed evenly, and sodium dodecyl sulfate was added for emulsification. After emulsification, ultrapure water was added and chloroform was removed by rotary evaporation. After centrifugation and alkaline water treatment, self-assembled near-infrared nanoparticles were obtained. The near-infrared nanoparticles consisted of an AIE core, a near-infrared quantum dot inner shell, and an outer shell uniformly distributed with the amphiphilic polymer and sodium dodecyl sulfate. The oleic acid-modified near-infrared quantum dots emitted wavelengths similar to those of the AIE dye.

2. The method for preparing high quantum yield core-shell-shell self-assembled near-infrared nanoparticles as described in claim 1, characterized in that: The near-infrared quantum dots are selected from PbS, PbSe, Ag2S, Ag2Se, CdTe, or CdS quantum dots.

3. The method for preparing high quantum yield core-shell-shell self-assembled near-infrared nanoparticles as described in claim 1, characterized in that, include: Dissolve 5 mg of amphiphilic polymer in chloroform, 6-12 mg of oleic acid-modified near-infrared quantum dots in chloroform, and 0.25-2 mg of AIE dye in chloroform. Mix the three thoroughly, then add 300 μL of 0.5 mg / mL sodium dodecyl sulfate for emulsification. After emulsification, add 3 mL of ultrapure water and rotary evaporate until no more bubbles emerge to remove the chloroform. Centrifuge at 12,000 rpm for 15 min. Add sodium hydroxide solution (pH=10) to the precipitate and treat for 12 hours. Centrifuge to remove the alkaline solution, add pure water, and store at 4 °C.

4. The method for preparing high quantum yield core-shell-shell self-assembled near-infrared nanoparticles as described in claim 3, characterized in that, The preparation method of the near-infrared quantum dots with oleic acid modified on the surface is as follows: ODE and OA are added to the cationic compound, the mixture is heated after vacuuming, and after the solid dissolves into a transparent liquid, the mixture is cooled under nitrogen protection; an anionic precursor solution is added and reacted, acetone is added, the upper liquid is removed after centrifugation, and then the mixture is washed with chloroform for later use.

5. The method for preparing high quantum yield core-shell-shell self-assembled near-infrared nanoparticles as described in claim 4, characterized in that: The cationic compound is selected from PbO, PbAc, AgAc, CdO, or CdAc.

6. The method for preparing high quantum yield core-shell-shell self-assembled near-infrared nanoparticles as described in claim 4, characterized in that: The anionic precursor is selected from (TMS)2Se / ODE, (TMS)2S / ODE, or TOP-Te.

7. The method for preparing high quantum yield core-shell-shell self-assembled near-infrared nanoparticles as described in claim 1, characterized in that: The amphiphilic polymer is selected from PMAO or DSPE-PEG.

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