Quantum dot seed micelles, quantum dot nanospheres, and methods of making and using the same

Abstract

The application discloses a quantum dot seed micelle, a quantum dot nanosphere and a preparation method and application thereof. The quantum dot seed micelle comprises quantum dots and an initiator complex coordinated with the quantum dots. The initiator complex is a dormant seed formed by covalence of a complex and a free radical of an initiator. Further, polymer monomers are subjected to temperature polymerization in an emulsified solution system with the quantum dot seed micelle, so that the quantum dot nanosphere is obtained. By introducing the initiator complex into the quantum dot seed micelle, the active center of the polymerization reaction is fixed on the surface of the quantum dots due to coordination in the process of preparing the quantum dot nanosphere, and the monomers continuously grow, so that the self-polymerization reaction of the monomers is reduced. Meanwhile, the dormant seed is formed by covalence of the complex and the free radical of the initiator, a reversible balance is formed, the free radical concentration and the chain termination rate are reduced, the inorganic part of the surface of the quantum dots is prevented from being oxidized, and thus the damage of the free radical of the initiator to the surface of the quantum dots is reduced.

Description

Technical Field

[0001] This invention relates to the field of quantum dot materials technology, and more specifically, to a quantum dot seed micelle, a quantum dot nanosphere, its preparation method, and its application. Background Technology

[0002] Quantum dots possess advantages such as tunable fluorescence emission wavelength, high photoluminescence quantum yield, and good fluorescence stability, making them highly favored for the quantitative detection of biomarkers such as proteins, nucleic acids, and cells. However, the small particle size and high surface energy of quantum dots make them prone to aggregation when used alone, leading to abnormal test results and limiting their application scenarios.

[0003] Encapsulating multiple quantum dots within a microsphere creates quantum dot fluorescent nanospheres. This provides a protective shell for the quantum dots, offering charged coupling groups, and the mutual repulsion of their surface potentials effectively prevents microsphere aggregation. Currently, most quantum dot nanosphere preparation methods first prepare quantum dot seed micelles, with the quantum dots being embedded during the preparation of uniformly sized nanospheres through copolymerization with monomers. However, during nanosphere preparation, monomers often undergo self-polymerization reactions, easily forming nucleation sites above the critical molecular weight, resulting in empty polymer spheres. This makes the separation and purification of quantum dot nanospheres challenging. Furthermore, commonly used free radical polymerization initiators in nanosphere preparation, such as persulfates and azo compounds, generate highly oxidizing free radicals upon decomposition, which can easily create defects on the quantum dot surface, thus affecting its fluorescence intensity.

[0004] In view of this, the present invention is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide quantum dot seed micelles, quantum dot nanospheres, their preparation methods and applications, in order to improve the above-mentioned technical problems.

[0006] This invention is implemented as follows:

[0007] In a first aspect, the present invention provides a quantum dot seed micelle comprising a quantum dot and an initiator complex coordinated with the quantum dot, wherein the initiator complex is a dormant seed formed covalently by the complex and an initiator radical.

[0008] Secondly, the present invention also provides a method for preparing the above-mentioned quantum dot seed micelles, which includes: mixing and dispersing quantum dots and initiator complexes uniformly in a solution system, wherein the solvent used in the solution system is a non-coordinating inert solvent.

[0009] Thirdly, the present invention also provides a quantum dot micelle dispersion, wherein the above-mentioned quantum dot seed micelles are dispersed in a non-coordinated inert solvent.

[0010] Fourthly, the present invention also provides a method for preparing quantum dot nanospheres, comprising: heating and polymerizing polymer monomers in a solution system containing the above-mentioned quantum dot seed micelles.

[0011] Fifthly, the present invention also provides a quantum dot nanosphere, which is prepared by the above-described method for preparing quantum dot nanospheres.

[0012] Sixthly, the present invention also provides the application of the above-mentioned quantum dot nanospheres in the preparation of biomarker detection reagents.

[0013] This invention offers the following advantages: By introducing an initiator complex into quantum dot seed micelles, the initiator complex can bind to the quantum dot surface. This allows the active centers of the polymerization reaction to be fixed on the quantum dot surface during the preparation of quantum dot nanospheres, enabling them to absorb monomers and continue growing, thereby reducing monomer self-polymerization. Simultaneously, the covalent formation of dormant species between the complex and the initiator's free radicals creates a reversible equilibrium, reducing free radical concentration and chain termination rate, preventing oxidation of the inorganic components on the quantum dot surface, and thus minimizing damage to the quantum dot surface caused by initiator free radicals. Attached Figure Description

[0014] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a TEM image of the quantum dot nanospheres of Example 1 of the present invention;

[0016] Figure 2 This is a TEM image of the quantum dot nanospheres of Example 2 of the present invention;

[0017] Figure 3 This is a TEM image of the quantum dot nanospheres of Example 3 of the present invention;

[0018] Figure 4 This is a TEM image of the quantum dot nanospheres of Example 4 of the present invention;

[0019] Figure 5 This is a TEM image of the quantum dot nanospheres from Example 5 of the present invention;

[0020] Figure 6 This is a TEM image of the quantum dot nanospheres of Example 6 of the present invention;

[0021] Figure 7This is a TEM image of the quantum dot nanospheres of Example 7 of the present invention;

[0022] Figure 8 This is a graph showing the change in the hydrated particle size of the quantum dot nanospheres in Example 7 of the present invention over time.

[0023] Figure 9 This is a TEM image of the quantum dot nanospheres of Example 8 of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0025] The following is a detailed description of the quantum dot seed micelles, quantum dot nanospheres, their preparation methods, and applications proposed in this invention.

[0026] Some embodiments of the present invention provide a quantum dot seed micelle comprising a quantum dot and an initiator complex coordinated with the quantum dot, wherein the initiator complex is a dormant seed formed by the free radical of the complex and the initiator.

[0027] By introducing an initiator complex into quantum dot seed micelles, where the initiator complex is a dormant species covalently formed by the complex and the initiator's free radicals, and the complex coordinates with the quantum dot surface, the initiator is fixed to the quantum dot surface. This means that when preparing quantum dot nanospheres using quantum dot seed micelles as raw material, the active center of the polymerization reaction is located on the quantum dot surface, allowing for the absorption and continuous growth of monomers, reducing the monomer self-polymerization reaction caused by the active center being located in the solvent. Simultaneously, the dormant species formed by the complex and the initiator's free radicals creates a reversible equilibrium, reducing the free radical concentration and chain termination rate, preventing the oxidation of the inorganic parts of the quantum dot surface, and thus minimizing the damage caused by initiator free radicals to the quantum dot surface.

[0028] It should be noted that the above inventive concept is to fix the initiator on the surface of the quantum dot through coordination, thereby fixing the active center of the polymerization reaction on the surface of the quantum dot. As long as the quantum dot and the complex can be coordinated and combined, and the complex can covalently form a dormant quantum dot seed bundle with the free radical of the initiator, it falls within the scope of protection of this application.

[0029] Specifically, in some embodiments, the complex is a haloalkane complex, which is a Z-type ligand. The quantum dots are inorganic metal semiconductor nanomaterials, specifically crystalline nanoparticles exhibiting size-dependent properties due to electronic state confinement effects. The haloalkane, acting as a Z-type ligand, binds to the surface of the quantum dots. The Z-type ligand, as a neutral two-electron acceptor (Lewis acid), binds to an occupied lone pair at the surface anion site (Lewis base).

[0030] In some embodiments, the haloalkane complex is a complex formed by a haloalkane and a metal ion, wherein the haloalkane can be a monohaloalkane; the structure of the haloalkane complex is RX-Me, where R is a C1-C10 alkyl group, preferably C5-C10 alkyl, more preferably octane, R can be branched or branched alkyl, X is a halogen, for example, Cl, Br or I, and Me is a metal ion selected from metal ions present on the surface of the quantum dot so that the band gap of the quantum dot does not change. For example, if the quantum dot is cadmium selenide nanocrystals, the metal ion is cadmium; if the quantum dot is silver sulfide nanocrystals, the metal ion is silver. If the quantum dot includes two metal ions, Me can be one of the metal ions; for example, if the quantum dot is cadmium selenide / zinc sulfide quantum dot, the metal ion can be zinc.

[0031] Furthermore, in some embodiments, the quantum dots include, but are not limited to, at least one of cadmium selenide nanocrystals, cadmium sulfide nanocrystals, silver sulfide nanocrystals, and zinc sulfide nanocrystals.

[0032] In some embodiments, the quantum dot surface contains vinyl ligands, which include, but are not limited to, at least one of olefinic ligands and acrylate ligands. That is, the vinyl ligands may be olefinic ligands alone, acrylate ligands alone, or both types of ligands may be present simultaneously.

[0033] Because the surface of quantum dots contains vinyl groups, the free radicals of the initiator can react with the vinyl groups on the surface of the quantum dots, increasing the molecular weight length and thus reducing the reactivity. This makes it difficult for the free radicals to attack the inorganic parts of the quantum dot surface, preventing the formation of defects on the quantum dot surface.

[0034] Specifically, olefinic ligands include, but are not limited to, at least one of n-octenic acid, n-nonenoic acid, and n-decenoic acid, while acrylate ligands include, but are not limited to, at least one of acrylates, methacrylates, or derivatives thereof. For example, acrylate ligands may be phosphate acrylate, ethylene glycol acrylate, propylene glycol methacrylate, or butylene glycol methacrylate, etc.

[0035] Furthermore, in some embodiments, the initiator is an oil-soluble azo initiator or a non-peroxide initiator. Peroxide initiator radicals readily coordinate with the quantum dot surface, forming surface defects and reducing the quantum yield of the quantum dots. Azo initiators include, but are not limited to, azobisisobutyronitrile (AIBN) and azobisisoheptanenitrile (AIHH).

[0036] Some embodiments of the present invention also provide a method for preparing quantum dot seed micelles, comprising: mixing and dispersing the above-mentioned quantum dots and the above-mentioned initiator complex in a solution system to form an oil phase mixture, wherein the solvent used in the solution system is a non-coordinating inert solvent. The use of a non-coordinating inert solvent is to ensure that the solvent does not affect the coordination structure between the initiator complex and the quantum dots.

[0037] The solubility parameter of the noncoordinating inert solvent is 21 to 25; for example, the noncoordinating inert solvent includes, but is not limited to, at least one of tetrachloroethane, pyridine, cyclohexanol, n-butanol, isobutanol, n-propanol, acetonitrile, and dimethylformamide.

[0038] Specifically, in some embodiments, an initiator complex solution and a quantum dot solution are first formed, and then the initiator complex solution and the quantum dot solution are mixed and dispersed.

[0039] The preparation process of the initiator complex solution is as follows: the initiator and the complex are dissolved in the aforementioned non-coordinating inert solvent. The mass ratio of the initiator to the complex in the initiator complex solution is (0.5–4):1, for example, 0.5:1, 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, or 4:1, etc. The ratio of the total mass of the initiator and the complex to the mass of the non-coordinating inert solvent in the initiator complex solution is 1:(5–10), for example, 1:5, 1:6, 1:7, 1:8, 1:9, or 1:10, etc.

[0040] The preparation process of quantum dot solution is as follows: a certain amount of quantum dots are dispersed in the above-mentioned non-coordinated inert solvent. The mass fraction of quantum dot solution can be 30% to 60%, for example, 30%, 35%, 40%, 45%, 50%, 55%, 58% or 60%, etc.

[0041] Because initiator free radicals have strong oxidizing properties, excessively high concentrations can cause irreversible oxidation reactions with inorganic surfaces, forming defect states. Therefore, in some embodiments, the mass ratio of quantum dot solution to initiator complex solution is (100-1000):1, for example, 100:1, 150:1, 200:1, 250:1, 300:1, 350:1, 400:1, 450:1, 500:1, 550:1, 600:1, 650:1, 700:1, 750:1, 800:1, 850:1, 900:1, 950:1, or 1000:1, etc.

[0042] Some embodiments of the present invention also provide a quantum dot micelle dispersion, wherein the quantum dot seed micelles of the above embodiments are obtained by emulsifying and dispersing in a non-coordinated inert solvent. That is, the quantum dot micelle dispersion can be obtained by dispersing the oil phase mixture in the above embodiments in an emulsifier solution. The emulsifier includes, but is not limited to, sodium dodecyl sulfate.

[0043] Furthermore, some embodiments of the present invention also provide a method for preparing quantum dot nanospheres, which includes: heating and polymerizing polymer monomers in an emulsion solution system containing the above-mentioned quantum dot seed micelles.

[0044] There are two traditional methods for supplying monomers. One is to introduce monomer droplets in a single step, where the monomer is gradually absorbed by micelles through diffusion. The diffusion rate decreases from fast to slow, and when the monomer droplets shrink to a certain size, they spontaneously nucleate to form empty polymer spheres. The other method is to continuously add monomer emulsions, where the added monomers are often at room temperature. High temperatures can cause the monomer emulsion to break down, and the monomers actually added to the reaction system remain in the form of monomer droplets. In some embodiments of this invention, to overcome the above technical problems, the polymer monomers are added in the form of monomer capsules. The monomer capsules are obtained by absorbing the polymer monomers into solid cross-linked porous microspheres. The monomer capsules act as a monomer library. They exist in the solution reaction system at the same temperature as the reaction and can continuously and slowly release polymer monomers under the centrifugal force of mechanical stirring. The polymer monomers are absorbed by quantum dot seed micelles, and the active polymerization centers are on the surface of the quantum dots. The polymer monomers do not spontaneously nucleate to form empty polymer spheres.

[0045] Continuing from the above, to ensure the slow release of polymer monomers, the polymerization is carried out under stirring conditions, with a stirring speed of 50–250 rpm, such as 50 rpm, 70 rpm, 90 rpm, 100 rpm, 120 rpm, 150 rpm, 175 rpm, 200 rpm, 225 rpm, 230 rpm, 240 rpm, or 250 rpm. Because quantum dot seed micelles have a high density, a stirring speed that is too slow is insufficient to suspend them, making it difficult for the monomers released from the monomer capsules to be absorbed. Conversely, a stirring speed that is too fast will result in an excessively rapid release of monomers, preventing uniform polymerization and growth on the quantum dot surface, thus leading to inconsistent particle size of the quantum dot nanospheres.

[0046] The preparation process of the monomer capsules is as follows: solid cross-linked porous microspheres are dispersed in a polymer monomer solution, allowing them to fully absorb the polymer monomers, and then filtered through a filter membrane to obtain monomer capsules. It should be noted that the solid cross-linked porous microspheres are commercially available cross-linked polymer microspheres with a particle size greater than 4 micrometers. The mass ratio of cross-linked porous microspheres to polymer monomers is greater than 1:2.

[0047] Furthermore, in some embodiments, the polymer monomer is a compound or a derivative thereof containing only one vinyl group; the polymer monomer includes, but is not limited to, at least one of styrene, chlorostyrene, methyl methacrylate, ethyl methacrylate, propyl acrylate and butyl acrylate.

[0048] In some embodiments, the above preparation method further includes filtering the solution after the heating polymerization reaction to obtain quantum dot nanospheres.

[0049] Some embodiments of the present invention also provide a quantum dot nanosphere, which is prepared by the preparation method of the quantum dot nanosphere of any of the above embodiments.

[0050] Some embodiments of the present invention also provide the application of quantum dot nanospheres in the preparation of biomarker detection reagents. These biomarker detection reagents can be used for the quantitative detection of biomarkers such as proteins, nucleic acids, and cells.

[0051] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0052] Example 1

[0053] This embodiment provides a method for preparing quantum dot nanospheres, the specific steps of which are as follows:

[0054] 1) 3.0 g of cadmium selenide quantum dots (synthesized by the method in reference CHEM.COMMUN.2003.2532-2533) were dispersed in 7.0 g of tetrachloroethane to obtain a quantum dot solution.

[0055] 2) Dissolve 0.01g of azobisisobutyronitrile and 0.02g of chlorooctane-cadmium in 0.3g of tetrachloroethane to form an initiator complex solution.

[0056] 3) Mix the quantum dot solution and the initiator complex solution obtained in the above two steps to form an oil phase mixture, add it to 100 mL of sodium dodecyl sulfate solution with a concentration of 1 mg / mL, and disperse it by ultrasonication to form a quantum dot micelle dispersion.

[0057] 4) Take 5g of solid cross-linked porous microspheres (Suzhou Nanomicro Technology Co., Ltd., 5 microns), disperse them in 10g of styrene until adsorption saturation, filter with a filter membrane to obtain styrene monomer capsules.

[0058] 5) Mix and disperse the quantum dot micelle dispersion and monomer capsules, stir at 50 rpm, polymerize at 70°C for 24 hours, and filter through a filter membrane to obtain the desired product. Figure 1 The quantum dot nanospheres shown do not have any empty nanospheres observed in the TEM image, PLQY = 91%.

[0059] Example 2

[0060] This embodiment provides a method for preparing quantum dot nanospheres, the specific steps of which are as follows:

[0061] 1) Disperse 6.0g of cadmium selenide quantum dots (same as in Example 1) in 3.93g of pyridine to obtain a quantum dot solution.

[0062] 2) Dissolve 0.08g of azobisisobutyronitrile and 0.02g of zinc bromooctane in 0.5g of pyridine to form an initiator complex solution.

[0063] 3) Mix the quantum dot solution and the initiator complex solution obtained in the above two steps to form an oil phase mixture, add it to 100 mL of sodium dodecyl sulfate solution with a concentration of 1 mg / mL, and disperse it by ultrasonication to form a quantum dot micelle dispersion.

[0064] 4) Take 10g of solid cross-linked porous microspheres (Suzhou Nanomicro Technology Co., Ltd., 10 microns), disperse them in 30g of methyl methacrylate until adsorption saturation, filter with a filter membrane to obtain methyl methacrylate monomer capsules.

[0065] 5) Mix and disperse the quantum dot micelle dispersion and monomer capsules, stir at 250 rpm, polymerize at 70°C for 24 hours, and filter through a filter membrane to obtain the desired product. Figure 2 The quantum dot nanospheres shown have a PLQY of 87.9%.

[0066] Example 3

[0067] This embodiment provides a method for preparing quantum dot nanospheres, the specific steps of which are as follows:

[0068] 1) Disperse 4.0g of cadmium selenide quantum dots (same as in Example 1) in 6.0g of n-butanol to obtain a quantum dot solution.

[0069] 2) Dissolve 0.01g of azobisisobutyronitrile and 0.02g of chlorooctane-cadmium in 0.3g of n-butanol to form an initiator complex solution.

[0070] 3) Mix the quantum dot solution and the initiator complex solution obtained in the above two steps to form an oil phase mixture, add it to 100 mL of sodium dodecyl sulfate solution with a concentration of 1 mg / mL, and disperse it by ultrasonication to form a quantum dot micelle dispersion.

[0071] 4) Take 10g of solid cross-linked porous microspheres (Suzhou Nanomicro Technology Co., Ltd., 5 microns), disperse them in 20g of styrene until adsorption saturation, filter with a filter membrane to obtain styrene monomer capsules.

[0072] 5) Mix and disperse the quantum dot micelle dispersion and monomer capsules, stir at 100 rpm, polymerize at 70°C for 24 hours, and filter through a filter membrane to obtain the desired product. Figure 3 The quantum dot nanospheres shown have a PLQY of 88.5%.

[0073] Example 4

[0074] This embodiment provides a method for preparing quantum dot nanospheres, the specific steps of which are as follows:

[0075] 1) Disperse 3.0g of cadmium selenide quantum dots (same as in Example 1) in 7.0g of tetrachloroethane to obtain a quantum dot solution.

[0076] 2) Dissolve 0.01g of azobisisoheptanenitrile and 0.02g of chlorodecane-cadmium in 0.3g of tetrachloroethane to form an initiator complex solution.

[0077] 3) Mix the quantum dot solution and the initiator complex solution obtained in the above two steps to form an oil phase mixture, add it to 100 mL of sodium dodecyl sulfate solution with a concentration of 1 mg / mL, and disperse it by ultrasonication to form a quantum dot micelle dispersion.

[0078] 4) Take 7g of solid cross-linked porous microspheres (Suzhou Nanomicro Technology Co., Ltd., 5 microns), disperse them in 14g of styrene until adsorption saturation, filter with a filter membrane to obtain styrene monomer capsules.

[0079] 5) Mix and disperse the quantum dot micelle dispersion and monomer capsules, stir at 150 rpm, polymerize at 60°C for 24 hours, and filter through a filter membrane to obtain the desired product. Figure 4 The quantum dot nanospheres shown have a PLQY of 84%.

[0080] Example 5

[0081] The only difference between this embodiment and Embodiment 1 is that cadmium selenide / cadmium sulfide quantum dots (purchased from Wuhan Jiayuan Quantum Dot Co., Ltd.) are used. Figure 5 As shown, the quantum dot does not contain vinyl ligands. Due to the poor compatibility between the quantum dot and polystyrene, an asymmetric structure is formed, and the quantum dot aggregates. The self-absorption phenomenon leads to a low PLQY (PLQY = 67.5%), and leakage is possible at any time.

[0082] Example 6

[0083] The only difference between this and Example 1 is that monomeric capsules are not used, such as... Figure 6 As shown in the TEM image, there are empty nanospheres with a particle size similar to that of quantum dot nanospheres, with PLQY = 89.4%.

[0084] Example 7

[0085] The only difference between this embodiment and Embodiment 1 is that the stirring speed in step 5 is 10 rpm. This stirring speed is too slow, making it difficult for the monomers to be released. Figure 7 As shown, the prepared nanospheres lack a distinct polymer shell and have a low PLQY (PLQY = 76%). Figure 8 As shown, the colloid has poor stability.

[0086] Example 8

[0087] The only difference between this embodiment and Embodiment 1 is that the stirring speed in step 5 is 500 rpm. Due to excessive centrifugal force, the monomers are rapidly released and aggregate into monomer droplets in the system. The liquid competes with the quantum dots for the adsorption initiator, thus self-aggregating into large hollow spheres, such as... Figure 9 As shown, PLQY = 77.6%.

[0088] In summary, the embodiments of the present invention can synthesize uniformly distributed and loaded quantum dot microspheres in one step. This is achieved by introducing an initiator complex into the quantum dot seed micelles. The complex binds to the quantum dot surface, and the complex and the initiator radicals covalently form dormant species, thus fixing the initiator to the quantum dot surface. During the preparation of quantum dot nanospheres, the active sites of the polymerization reaction can be located on the quantum dot surface, allowing the polymer monomers to grow continuously on the quantum dot surface, avoiding monomer self-polymerization caused by the active sites being located in the solvent. Simultaneously, because the complex and the initiator radicals covalently form dormant species, a reversible equilibrium is established, reducing the radical concentration and chain termination rate, preventing the inorganic parts of the quantum dot surface from being oxidized, thereby reducing defects caused by initiator radical damage to the quantum dot surface.

[0089] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A quantum dot seed micelle, characterized in that, The quantum dot seed micelles include quantum dots and an initiator complex that is coordinated with the quantum dots, wherein the initiator complex is a dormant seed formed by the complex and the initiator free radical covalently. The complex is a haloalkane complex, which is a complex formed by a haloalkane and a metal ion, and the haloalkane complex is a Z-type ligand; the structure of the haloalkane complex is RX-Me, where R is a C1-C10 alkyl group, X is a halogen, and Me is a metal ion, and the metal ion is selected from the metal ions present on the surface of the quantum dot.

2. The quantum dot seed micelles according to claim 1, characterized in that, The quantum dots are inorganic metal semiconductor nanomaterials, and are crystalline nanoparticles exhibiting size-dependent properties due to electronic state confinement effects. The haloalkane is a monohaloalkane; the alkyl group is a C5-C10 alkyl group. The quantum dots include at least one of cadmium selenide nanocrystals, cadmium sulfide nanocrystals, silver sulfide nanocrystals, and zinc sulfide nanocrystals. The initiator is an oil-soluble azo initiator.

3. The quantum dot seed micelles according to claim 2, characterized in that, The alkyl group is octane; the surface of the quantum dot contains vinyl ligands, which include at least one of olefinic ligands and acrylate ligands.

4. The seed micelles according to claim 3, characterized in that, The olefinic ligands include at least one of n-octenic acid, n-nonenoic acid, and n-decenoic acid, and the acrylate ligands include at least one of acrylates, methacrylates, or derivatives thereof.

5. The method for preparing quantum dot seed micelles according to any one of claims 1-4, characterized in that, It includes: The quantum dots and the initiator complex are mixed and dispersed uniformly in a solution system, wherein the solvent used in the solution system is a non-coordinating inert solvent; The preparation method includes: first forming an initiator complex solution and a quantum dot solution, respectively, and then mixing and dispersing the initiator complex solution and the quantum dot solution; The preparation process of the initiator complex solution is as follows: the initiator and the complex are dissolved in the non-coordinating inert solvent.

6. The preparation method according to claim 5, characterized in that, The mass ratio of initiator to complex in the initiator complex solution is (0.5~4):1; the ratio of the total mass of the initiator and the complex to the mass of the non-coordinate inert solvent in the initiator complex solution is 1:(5~10). The quantum dot solution has a mass fraction of 30% to 60%. The mass ratio of the quantum dot solution to the initiator complex solution is (100~1000):1; The solubility parameter of the noncoordinate inert solvent is 21~25.

7. The preparation method according to claim 6, characterized in that, The noncoordinating inert solvent includes at least one of tetrachloroethane, pyridine, cyclohexanol, n-butanol, isobutanol, n-propanol, acetonitrile, and dimethylformamide.

8. A quantum dot micelle dispersion, characterized in that, It is obtained by emulsifying and dispersing quantum dot seed micelles as described in any one of claims 1-4 in a non-coordinated inert solvent.

9. A method for preparing quantum dot nanospheres, characterized in that, It includes: The polymer monomer is subjected to heated polymerization in an emulsion solution system containing quantum dot seed micelles, wherein the quantum dot seed micelles are the quantum dot seed micelles according to any one of claims 1-4.

10. The method for preparing quantum dot nanospheres according to claim 9, characterized in that, The polymer monomer is added in the form of monomer capsules, which are obtained by absorbing the polymer monomer in solid cross-linked porous microspheres; The polymer monomer is a compound or a derivative thereof that contains only one vinyl group; The solid cross-linked porous microspheres have a particle size greater than 4 micrometers.

11. The method for preparing quantum dot nanospheres according to claim 9, characterized in that, The polymer monomers include at least one of styrene, chlorostyrene, methyl methacrylate, ethyl methacrylate, propyl acrylate, and butyl acrylate.

12. The preparation method according to claim 9, characterized in that, The heating polymerization is carried out under stirring conditions, with a stirring speed of 50~250 rpm. After the polymerization reaction is heated, the solution is filtered.

13. A quantum dot nanosphere, characterized in that, It is prepared by the preparation method described in any one of claims 9 to 12.

14. The application of the quantum dot nanospheres as described in claim 13 in the preparation of biomarker detection reagents.

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