阅读说明：本技术 一种光学复合金属纳米材料的制备方法和应用 (Preparation method and application of optical composite metal nano material ) 是由 王晓英 金鑫 宫苗 吕良瑞 李淋雨 陈晴晴 顾璇 于 2019-11-14 设计创作，主要内容包括：本发明公开一种光学复合金属纳米材料的制备方法和应用,该方法步骤为：先将壳聚糖、重金属盐、氢氧化钠、联吡啶钌和分散剂在室温下混合研磨,然后加入氯金酸/氯铂酸/氯钯酸溶液或其盐溶液继续研磨,直至产物颜色变为棕色,将产物离心洗涤即得XRuY光学复合金属纳米材料。本发明通过研磨制得的光学复合金属纳米材料尺寸较小且均一,制备过程耗时较少,该法可在室温下进行,不需要额外条件,简便、快速且环保；且本发明制备的光学复合金属纳米材料具有非常好的稳定性,发光效率显著增高、导电性能和生物相容性良好,可应用于电致化学发光生物传感器,作为电极修饰或标记材料,为生物分子的分析检测提供新途径。(The invention discloses a preparation method and application of an optical composite metal nano material, wherein the method comprises the following steps: firstly, mixing and grinding chitosan, heavy metal salt, sodium hydroxide, bipyridyl ruthenium and a dispersing agent at room temperature, then adding chloroauric acid/chloroplatinic acid/chloropalladite solution or salt solution thereof, continuously grinding until the color of the product becomes brown, and centrifugally washing the product to obtain the XRuY optical composite metal nano material. The optical composite metal nano material prepared by grinding has small and uniform size, the time consumption of the preparation process is less, the method can be carried out at room temperature, additional conditions are not needed, and the method is simple, convenient, rapid and environment-friendly; the optical composite metal nano material prepared by the invention has good stability, obviously improved luminous efficiency and good conductivity and biocompatibility, can be applied to an electrochemiluminescence biosensor, can be used as an electrode modification or labeling material, and provides a new path for analysis and detection of biomolecules.)

1. A method for preparing optical composite metal nano material is characterized by comprising the following steps: firstly, mixing and grinding chitosan, heavy metal salt, sodium hydroxide, bipyridyl ruthenium and a dispersing agent at room temperature, then adding chloroauric acid/chloroplatinic acid/chloropalladite solution or salt solution thereof, continuously grinding until the color of a product becomes brown, and centrifugally washing the product to obtain the XRuY optical composite metal nano material; wherein the heavy metal salt is metal X salt with density of 4.5g/cm³The heavy metal Y is gold, platinum or palladium.

2. The method of claim 1, wherein the heavy metal salt is a silver salt, an iron salt, or a copper salt.

3. The method for preparing an optical composite metal nano-material according to claim 1, wherein the mass ratio of the heavy metal salt, ruthenium bipyridine to chloroauric acid/chloroplatinic acid/chloropalladic acid or salts thereof is 1-40: 1-15: 1-50.

4. The method for preparing an optical composite metal nano-material according to claim 3, wherein the mass ratio of the heavy metal salt, ruthenium bipyridyl to chloroauric acid/chloroplatinic acid/chloropalladic acid or salts thereof is 1-10: 1-5: 1-15.

5. The method for preparing the optical composite metal nano-material according to claim 1, wherein the addition amount of each raw material is, in mass percent: 47-69% of chitosan powder, 0.4-16% of heavy metal salt powder, 20-29% of sodium hydroxide powder, 0.4-6% of bipyridine ruthenium powder, 0.3-0.5% of dispersing agent and 0.4-20% of chloroauric acid/chloroplatinic acid/chloropalladic acid or salts thereof.

6. The method of claim 1, wherein the dispersant is a negatively charged surfactant.

7. The method for preparing an optical composite metal nanomaterial according to claim 6, wherein the dispersant is an alkylsulfonate.

8. The method for preparing an optical composite metal nanomaterial according to claim 1, wherein the concentration of the chloroauric acid/chloroplatinic acid/chloropalladic acid solution or the salt solution thereof is not less than 1g/mL, and the addition amount thereof is not more than 50 μ L.

9. The method for preparing an optical composite metal nanomaterial according to claim 1, wherein the time for mixing and grinding the chitosan, the heavy metal salt, the sodium hydroxide, the bipyridyl ruthenium and the dispersing agent is not less than 7min, and the time for grinding after adding the chloroauric acid/chloroplatinic acid/chloropalladic acid solution or the salt solution thereof is not less than 13 min.

10. Use of the optical composite metal nanomaterial prepared according to claim 1 as a biomolecular marker for ECL biosensors.

Technical Field

The invention relates to a preparation method of an optical composite metal nano material and application of the optical composite metal nano material prepared by the method as an ECL biosensor biomolecule marker, belonging to the field of photoelectric material manufacturing.

Background

Bipyridine ruthenium (Ru (bpy)₃ ²⁺Abbreviated as Ru) has the characteristics of stable chemical property, wide application pH range, high luminous efficiency, reversible electrochemical behavior and the like, and is the ECL (Electrochemiluminescence) active substance which is most widely applied. In recent years, Ru (bpy)₃ ²⁺And their derivatives are more studied as anchoring materials. The fixing material includes a nano material made of metal, semiconductor, carbon, polymer, etc., and a composite thereof. Wherein, the metal nanometer material has surface plasma resonance and better conductivity, and can enhance Ru (bpy)₃ ²⁺Thereby improving the sensitivity of the ECL biosensor, is that the current immobilized Ru (bpy)₃ ²⁺More popular vectors.

Metal nanomaterials can be divided into monometallic and polymetallic composites. The multi-metal compound is formed by compounding two or more metals in a nano-scale size (1-100 nm) at least in one direction. Therefore, the optical composite metal nano material is prepared by mixing the multi-metal composite with Ru (bpy)₃ ²⁺In combination, the following advantages are achieved: (1) not only can keep the advantages of a single metal nano material, but also can well show the synergistic effect of a plurality of nano materials; (2) has larger specific surface area, can enlarge Ru (bpy)₃ ²⁺The amount of solid carried; (3) readily absorb energy to produce an excited state, thereby amplifying Ru (bpy)₃ ²⁺A signal. Therefore, the optical composite metal nano material is widely applied to the research of ECL biosensors.

At present, the synthesis methods of the optical composite metal nano material comprise a blending method, an in-situ polymerization method, a sol-gel method, a coating precipitation method and the like, the methods need to be carried out in solution, the preparation procedure is complex, the production cost is high, and certain pollution is caused to the environment.

Disclosure of Invention

The purpose of the invention is as follows: aiming at the problems that the existing synthesis methods are required to be carried out in solution, the preparation procedures are complex, the production cost is high, the environment is polluted and the like, the invention provides a preparation method of an optical composite metal nano material, and also provides an application of the optical composite metal nano material prepared by the method.

The technical scheme is as follows: the invention relates to a preparation method of an optical composite metal nano material, which comprises the following steps: mixing and grinding the polysaccharide, the heavy metal salt, the sodium hydroxide, the bipyridyl ruthenium and the dispersing agent at room temperature, adding chloroauric acid/chloroplatinic acid/chloropalladite solution or salt solution thereof, continuing grinding until the color of the product is brown, and centrifugally washing the product to obtain the XRuY optical composite metal nano material; wherein the heavy metal salt is metal X salt with density of 4.5g/cm³The heavy metal Y is gold, platinum or palladium. Because the material contains bipyridyl ruthenium, the material needs to be stored in a dark place.

In the XRuY optical composite metal nanomaterial, Ru is an abbreviation for bipyridine ruthenium, which is used as an Electrochemiluminescence (ECL) active substance and is a source of an ECL signal. X is heavy metal, can load luminescent substance bipyridyl ruthenium, and can enhance the conductivity of the material, preferably, X can be silver, copper, iron and the like, correspondingly, the raw material heavy metal salt for providing X is silver salt, copper salt and iron salt, such as silver nitrate, silver chloride, copper nitrate, ferric sulfate and the like. Y (gold, platinum or palladium) can load luminescent substance bipyridyl ruthenium, enhance the conductivity of the material and provide the biocompatibility of the material, and is provided by chloroauric acid/chloroplatinic acid/chloropalladic acid or salts thereof, and the chloroauric acid/chloroplatinic acid/chloropalladic acid or the salts thereof are easy to deliquesce and are respectively prepared into a chloroauric acid solution, a chloroplatinic acid solution, a chloropalladic acid solution or a salt solution of the chloroauric acid, the chloroplatinic acid and the chloropalladic acid for use.

Wherein the mass ratio of the heavy metal salt, the ruthenium bipyridyl to the chloroauric acid/chloroplatinic acid/chloropalladic acid or the salts thereof is preferably 1-40: 1-15: 1-50. Further, the mass ratio of the heavy metal salt, the ruthenium bipyridyl to the chloroauric acid/chloroplatinic acid/chloropalladic acid or the salts thereof is 1-10: 1-5: 1-15. The proportions are based on the mass of the solute chloroauric acid/chloroplatinic acid/chloropalladic acid or salts thereof, rather than the mass of the chloroauric acid/chloroplatinic acid/chloropalladic acid solution or salt solution thereof after preparation into a solution. Preferably, the concentration of the chloroauric acid/chloroplatinic acid/chloropalladite solution or the salt solution thereof is not lower than 1g/mL, and the adding amount thereof is not more than 50 μ L.

Preferably, the addition amount of the raw materials is as follows by mass percent: 47-69% of chitosan powder, 0.4-16% of heavy metal salt powder, 20-29% of sodium hydroxide powder, 0.4-6% of bipyridine ruthenium powder, 0.3-0.5% of dispersing agent and 0.4-20% of chloroauric acid/chloroplatinic acid/chloropalladic acid or salts thereof.

The dispersing agent is a surfactant with negative electricity, the bipyridyl ruthenium carries positive electricity, and the dispersing agent can be coated on the surface of the metal particles in an adsorption manner to prevent the metal particles from agglomerating; the dispersant preferably adopts alkyl sulfonate such as sodium dodecyl sulfate and the like, the alkyl sulfonate is adsorbed and coated on the surface of the metal particles, and the bipyridyl ruthenium is further immobilized under the electrostatic action of positive and negative charges.

When grinding, the mixing and grinding time of the chitosan, the heavy metal salt, the sodium hydroxide, the bipyridyl ruthenium and the dispersing agent is preferably not less than 7min, and the grinding time after adding the chloroauric acid/chloroplatinic acid/chloropalladate solution or the salt solution thereof is preferably not less than 13 min.

The application of the optical composite metal nano material prepared by the method is to use the optical composite metal nano material prepared by the method as an ECL biosensor biomolecule marker.

The related abbreviations in the present invention are as follows:

nanometal X (XNPs)

Nano metal Y (YNPs)

Chloroauric acid (HAuCl)₄) Chloroplatinic acid (HPtCl)₄) Chloropalladate (HPdCl)₄)

Optical composite metal nanometer material (XNPs-Ru (bpy)₃ ²⁺-YNPs, abbreviated XRuY)

Electrochemiluminescence coreactant tripropylamine (TPrA)

Cyclic voltammetric scanning (CV)

Electrochemiluminescence scanning (ECL)

Silver-silver chloride reference electrode (Ag/AgCl)

Transmission Electron Microscope (TEM)

Field Emission Scanning Electron Microscope (FESEM)

Fluorescence inverted microscope (IFM)

The invention principle is as follows: the invention adopts a grinding method to compound two or more than two kinds of nano particles, in the grinding process, the mother particles generate circular deformation under the action of various acting forces, large-angle crystal boundaries in the particles can be recombined, the organization structure of the powder is gradually refined, and the aim of mutually permeating and diffusing atoms of different components is finally achieved. Chitosan is used as a reducing agent, metal X ions can be reduced into an X simple substance, and X atoms can be further combined with Y atoms after being formed; in addition, chitosan has amino and hydroxyl groups, and thus has adsorbability and polycationicity, so that metal X prepared using it adsorbs a large amount of Ru (bpy)₃ ²⁺Thereby forming XRuY;

XY adsorbs more positively charged Ru (bpy) relative to the YNPs structure₃ ²⁺Ru (bpy) thus adsorbed on the XY Structure₃ ²⁺An increased amount of can result in more complexes participating in ECL reactions on the electrode surface, resulting in enhanced ECL signal; moreover, rapid electron transfer through a bimetallic interface allows Ru (bpy)₃ ²⁺To facilitate Ru (bpy)₃ ²⁺The formation of an excited state causes the ECL initial voltage to be significantly negatively shifted, so that the photoelectric efficiency is enhanced;

in addition, XRuY retains the excellent electron transfer capacity of XNPs and YNPs, and the oriented connection between the components of the XNPs and the YNPs provides an electron 'expressway' for rapid electron migration through a bimetallic interface, accelerates the electron transfer rate, and therefore has good conductivity;

in addition, the optical composite metal nano material contains two metals of X and Y, so that the specific surface area of the optical composite metal nano material is larger than that of a single metal. Meanwhile, because the covalent coupling action exists between the metal and the biological molecules, the metal can be directly combined with the biological molecules without adding any coupling agent, thereby solving the problem of Ru (bpy)₃ ²⁺No functional group can crosslink the defect of the biological molecule. Therefore, the material has better biocompatibility and can be widely used as a marking material.

Has the advantages that: compared with the prior art, the invention has the advantages that: (1) the optical composite metal nano material prepared by grinding has small and uniform size, the time consumption of the preparation process is less, and the method can be carried out at room temperature without additional conditions, is simple, convenient, quick and environment-friendly; (2) the optical composite metal nano material prepared by the method has good stability, and ECL signals of the optical composite metal nano material are almost unchanged after 30 CV cyclic scanning; when the protein is used as a marker and fixed on an electrode, after the protein is stored in a phosphate buffer solution at 4 ℃ for 15 days, an ECL signal is almost unchanged and is reduced to below 90 percent after 17 days; (3) the optical composite metal nano material obtained by the optical composite metal nano material provided by the invention has the advantages of multiple metal nano materials, can overcome the defects of the existing method, obtains a novel photoelectric material with remarkably improved luminous efficiency (for example, the ECL signal of AgRuAu is about 1.3 times higher than that of a single metal ruthenium-doped nano material under the same condition), and good conductivity and biocompatibility, can be applied to an ECL biosensor, can be used as an electrode modification or marking material, and provides a way for detecting biomolecules.

Drawings

FIG. 1 is an ECL, DPV and TEM characterization of AgRuAu prepared in example 1;

FIG. 2 shows AgRuAu and Ru (bpy) prepared in example 1₃ ²⁺XRD pattern of (a);

curves a-d in FIG. 3 are ECL profiles of AgAu, AgRu, AuRu and AgRuAu, respectively, in 1.0mM TPrA-10mM PBS (pH7.3);

figure 4 shows the stability data of AgRuAu as a label immobilized on the electrode.

Detailed Description

The technical scheme of the invention is further explained by combining the attached drawings.

According to the preparation method of the optical composite metal nano material, the optical composite metal nano material is prepared by carrying out solid-phase grinding by adopting a small mortar, and the method can be carried out at room temperature without additional conditions such as heating; and the prepared optical composite metal nano material has small and uniform size and consumes less time in the preparation process. Therefore, the method is simple, convenient, rapid and environment-friendly.