Chiral noble metal nanocage induced and synthesized by utilizing penicillamine as well as preparation method and application of chiral noble metal nanocage

Abstract

The invention discloses a chiral precious metal nanocage induced and synthesized by penicillamine and a preparation method and application thereof, precious metals in the chiral precious metal nanocage are palladium, platinum and gold, the molar ratio of palladium to platinum to gold is (16-18): (24-28): (56-59), and the chiral precious metal nanocage has three-dimensional chiral morphology characteristics induced by penicillamine chiral molecules. And the edge length is in a nanometer size. Chiral deposition growth of gold atoms in two palladium-platinum nanometer hollow frame structures (cubes and icosahedrons) is induced through chiral penicillamine molecules (D- / L-penicillamine), and a chiral precious metal palladium-platinum-gold three-element hollow nanometer cage structure is constructed. The structure shows excellent catalytic activity on selective catalytic oxidation of D-configuration glucose molecules. The invention provides an efficient, low-cost and high-reliability biomimetic catalytic material solution for glucose detection, and promotes the upgrading of diabetes management, biosensing and food quality control technologies.

Description

Technical Field

[0001] The present invention belongs to the technical field of catalysts, and in particular relates to a chiral noble metal nanocage synthesized by induction with penicillamine, and a preparation method and application thereof. Background Art

[0002] Accurate glucose detection is crucial in diabetes management, biosensing, and the food industry. Currently, the widely used glucose oxidase relies on a natural enzyme catalytic reaction pathway. Although it has a good catalytic effect, it also has inherent defects: (1) poor environmental stability, easily affected by temperature and pH, and easily inactivated during long-term storage; (2) high cost, complex natural enzyme extraction and purification processes, and limited large-scale application; (3) inflexible controllability, difficult to perform surface modification, and difficult to adapt to complex and diverse application scenarios. Therefore, the development of efficient and stable biomimetic catalytic materials to replace natural glucose oxidase has become an urgent need.

[0003] In recent years, precious metal nanomaterials (such as gold, platinum, palladium, etc.) have attracted much attention due to their enzyme-like catalytic activity. For example: (1) Single metal nanoparticles (such as gold nanoparticles) exhibit glucose oxidase-like and peroxidase-like activities, but the overall catalytic efficiency is low (Nat. Commun. 2021, 12, 3375); (2) Bimetallic alloys (such as palladium-platinum) enhance peroxidase-like catalytic activity through synergistic effects, but still have problems such as insufficient exposure of active sites and poor catalytic selectivity (Small 2024, 20, 2309704); (3) Traditional solid nanostructures (such as solid spheres and rod-like morphologies) have limited specific surface area, and the proportion of highly catalytically active atoms on the surface is low, which limits the mass transfer efficiency of the catalytic substrate (Chem. Rev. 2021, 121, 796). Therefore, how to achieve highly active and highly selective functional enzyme mimics through structural design and component optimization remains a technical difficulty in the synthesis and preparation of inorganic enzyme catalysts.

[0004] On the other hand, chiral nanomaterials, due to their unique spatial configuration, can enhance the selective recognition and catalysis of specific chiral substrates through chiral matching. For example, glucose molecules have two molecular configurations, D- / L-, which are mirror images of each other. When the nanocatalyst material with chiral configuration matches the D- / L-chiral substrate molecule, the catalytic effect can be enhanced. However, the existing technology for synthesizing chiral nanomaterials has the following inherent defects: (1) The synthesis of chiral nanomaterials mostly relies on the modification of surface chiral recognition molecules (such as chiral compounds such as DNA, amino acids or peptides), and the source of their enantiocatalytic selectivity is only through the chiral recognition molecules on the surface, so the catalytic enantioselectivity is low and there is still a lot of room for improvement (Angew. Chem. Int. Ed. 2018, 57, 16791); (2) The chiral structure is not stable enough, or once the surface-modified chiral molecules fall off, the chiral configuration collapses easily during the reaction, resulting in a decrease in catalytic enantioselectivity or complete disappearance; (3) There is a lack of research on the coordinated design of chiral induction and catalytic active sites, making it difficult to achieve functional simulation of efficient enzyme catalysis.

[0005] In summary, existing chiral glucose mimetic enzyme technology faces the following core problems: poor stability of natural enzymes, and unsatisfactory catalytic efficiency and selectivity of nano-mimic enzymes; the preparation of chiral materials relies on simple modification of simple surface chiral recognition molecules, and is difficult to synergistically optimize with catalytic activity; the controllable synthesis and chiral functionalization of multi-noble metal catalysts with highly catalytically active surfaces have not yet been achieved. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention provides a chiral noble metal nanocage synthesized using penicillamine, as well as its preparation method and application. Chiral penicillamine molecules (D- / L-penicillamine) induce the chiral deposition and growth of gold atoms within two palladium-platinum hollow nanostructures (pd-platinum cubes and icosahedrons), thereby constructing a chiral noble metal palladium-platinum-gold hollow nanocage structure. This structure also exhibits excellent catalytic activity for the selective oxidation of D-glucose molecules.

[0007] The present invention is achieved through the following technical solutions:

[0008] A chiral noble metal nanocage synthesized by induction using penicillamine, wherein the noble metals in the chiral noble metal nanocage are palladium, platinum, and gold, and the molar ratio of the three is (16-18):(24-28):(56-59). The chiral noble metal nanocage has a three-dimensional chiral morphology induced by the chiral penicillamine molecule, and the edge length is in the nanometer size.

[0009] Preferably, the chiral noble metal nanocages include D-configuration cubic palladium platinum gold nanocages, L-configuration cubic palladium platinum gold nanocages, D-configuration icosahedral palladium platinum gold nanocages, and L-configuration icosahedral palladium platinum gold nanocages.

[0010] The preparation method of the chiral noble metal nanocage synthesized by induction of penicillamine comprises the following steps:

[0011] Step 1) synthesizing nanoscale palladium cubic or icosahedral solid nanoparticles;

[0012] step 2) depositing platinum atoms on the palladium nanocubes or icosahedrons prepared in step 1) to form palladium-platinum cubic or icosahedral nanoparticles with a core-shell structure;

[0013] step 3) selectively etching the palladium core inside the palladium-platinum cubic or icosahedral nanoparticles prepared in step 2) using an aqueous solution system of ferric chloride, potassium bromide, and hydrochloric acid to obtain hollow palladium-platinum nanocubes or icosahedral frameworks;

[0014] Step 4) chiral D- / L-penicillamine molecules are used to induce gold atoms to deposit and grow on the palladium-platinum nanocube or icosahedral framework prepared in step 3), thereby constructing a chiral palladium-platinum hollow nanocage structure.

[0015] Preferably, the specific steps of step 1) are as follows: dissolving polyvinyl pyrrolidone, ascorbic acid and potassium bromide in a solvent to obtain a surfactant + reducing agent solution, wherein the concentration of polyvinyl pyrrolidone is 13-40 mg / mL, the concentration of ascorbic acid is 0-7.5 mg / mL, and the concentration of potassium bromide is 0-75 mg / mL; then dissolving sodium tetrachloropalladate in a solvent to obtain a palladium metal salt precursor solution, wherein the concentration of sodium tetrachloropalladate is 15.5-18.7 mg / mL; then, under heating conditions, mixing the surfactant + reducing agent solution and the palladium metal salt precursor solution to prepare palladium crystal seeds with cubic or icosahedral morphology; centrifuging, removing the supernatant, and redispersing to obtain an ethylene glycol solution in which palladium nanocubes or icosahedral particles are dispersed.

[0016] Preferably, when the chiral noble metal nanocage is a cube, the solvent is deionized water; when the chiral noble metal nanocage is an icosahedron, the solvent is diethylene glycol.

[0017] Preferably, the specific steps of step 2) are as follows: dissolving polyvinyl pyrrolidone, ascorbic acid and potassium bromide in an ethylene glycol solution to obtain a surfactant + reducing agent solution, wherein the concentration of polyvinyl pyrrolidone is 12.5 mg / mL, the concentration of ascorbic acid is 6.25 mg / mL, and the concentration of potassium bromide is 10 mg / mL; then adding the ethylene glycol solution in which the palladium nanocubes or icosahedral particles prepared in step 1) are dispersed to the surfactant + reducing agent solution to obtain a reaction system solution; then dissolving sodium hexachloroplatinate in ethylene glycol to prepare a sodium hexachloroplatinate solution with a concentration of 0.58 to 1 mg / mL, gradually injecting the sodium hexachloroplatinate solution dropwise into the reaction system solution to react, centrifuging, removing the supernatant, and redispersing to obtain an aqueous solution in which core-shell structured palladium-platinum nanocubes or icosahedral particles are dispersed.

[0018] Preferably, the specific steps of step 3) are as follows: adding the aqueous solution in which the core-shell structured palladium-platinum nanocubes or icosahedral particles prepared in step 2) are dispersed to an aqueous system containing ferric chloride, potassium bromide, hydrochloric acid and polyvinyl pyrrolidone and mixing them thoroughly. After continuous constant temperature reaction, the mixture is centrifuged, the supernatant is removed, and the mixture is redispersed to obtain an N,N-dimethylformamide solution in which hollow cubic or icosahedral palladium-platinum nanocages are dispersed.

[0019] Preferably, the specific steps of step 4) are as follows: dissolving polyvinyl pyrrolidone, chloroauric acid, and D- / L-penicillamine in an N,N-dimethylformamide solution, wherein the concentration of polyvinyl pyrrolidone is 70 mg / mL, the concentration of chloroauric acid is 0.3 mM, and the concentration of D- / L-penicillamine is 80 μM; then adding the N,N-dimethylformamide solution in which the cubic or icosahedral palladium-platinum nanocages prepared in step 3) are dispersed, mixing and heating to react, then centrifuging, removing the supernatant, and redispersing to obtain an aqueous solution system in which chiral D- / L-configuration cubic or icosahedral palladium-platinum hollow nanocages are dispersed.

[0020] Application of the chiral noble metal nanocages or the chiral noble metal nanocages prepared by the above preparation method in glucose detection.

[0021] Preferably, the chiral noble metal nanocage is used as a glucose functional mimicking enzyme catalyst.

[0022] The beneficial effects of the present invention are as follows:

[0023] (1) The present invention utilizes the intrinsic chiral center of the D- / L-penicillamine molecule to directly guide gold atoms to form a microenvironment with specific chiral crystal faces on the surface of the palladium-platinum nanoframe, endowing the nanocage with intrinsic chiral catalytic activity. Compared with traditional surface-modified chiral materials, the present invention significantly enhances the "lock-and-key" selective recognition ability of D- / L-glucose by embedding the atomic-level chiral configuration, significantly improving the catalytic enantioselectivity and effectively avoiding interference from other isomers, laying the foundation for accurate detection in complex biological samples (such as serum and food matrices).

[0024] (2) The present invention maximizes the exposure of catalytic active sites through the electronic synergistic effect of the palladium-platinum-gold ternary metal and the hollow porous structure design. First, the specific surface area of ​​the hollow nanocage structure (cube and icosahedron) is significantly higher than that of traditional solid nanoparticles, effectively promoting the efficient adsorption and diffusion of glucose molecules; second, the palladium-platinum alloy framework provides a stable catalytic substrate, and the chiral deposition of gold atoms on the surface forms a highly active crystal face rich in steps / defects, which significantly improves the glucose oxidase-like activity compared to single-metal gold nanoparticles; third, the peroxidase-like activity of the palladium-platinum alloy cooperates with the oxidase-like activity of gold to achieve efficient catalysis of the glucose oxidation cascade reaction, with a detection sensitivity of 0.05 Abs / mM and a minimum detection limit of 74 μM, which is better than most reported enzyme-based sensors.

[0025] (3) This invention utilizes a wet chemical colloid synthesis strategy, which precisely regulates the size, morphology, and chiral orientation of the nanocage by controlling the chiral configuration of penicillamine, the ratio of metal precursors, and the reduction kinetics. Compared to natural enzyme extraction processes, the present invention offers a simpler synthesis route, eliminates the need for complex purification steps, and significantly reduces the cost of large-scale production, paving the way for industrial applications.

[0026] (4) The chiral noble metal nanocage structure of the present invention tolerates a wide pH range and high temperature environment and can be stored for a long time, completely overcoming the defect of natural enzymes being easily inactivated.

[0027] (5) The present invention achieves the synergistic enhancement of chirality, activity and stability for the first time through the three-in-one strategy of "chirality induction-structure design-component optimization", providing an efficient, low-cost and highly reliable biomimetic catalytic material solution for glucose detection, and promoting the upgrading of diabetes management, biosensing and food quality control technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1Transmission electron micrographs of the cubic chiral palladium-platinum hollow nanocages prepared in Example 1: A is a bright-field transmission electron micrograph of the overall D-configuration cubic hollow nanocage; B is a bright-field transmission electron micrograph of the overall L-configuration cubic hollow nanocage; C is a dark-field transmission electron micrograph of a single D-configuration cubic hollow nanocage; D is a dark-field transmission electron micrograph of a single L-configuration cubic hollow nanocage;

[0029] Figure 2 Element distribution diagram of the L-configuration cubic palladium platinum hollow nanocage prepared in Example 1;

[0030] Figure 3 Transmission electron micrographs of the icosahedral chiral palladium-platinum hollow nanocages prepared in Example 2: A is a bright-field transmission electron micrograph of the overall D-configuration icosahedral hollow nanocage; B is a bright-field transmission electron micrograph of the overall L-configuration icosahedral hollow nanocage; C is a dark-field transmission electron micrograph of a single D-configuration icosahedral hollow nanocage; D is a dark-field transmission electron micrograph of a single L-configuration icosahedral hollow nanocage;

[0031] Figure 4 Element distribution diagram of the L-configuration icosahedral palladium platinum hollow nanocage prepared in Example 2;

[0032] Figure 5 These are the effects of the D-configured cubic palladium-platinum hollow nanocage catalyzing D-glucose in Example 3: A is the UV spectrum of D-configured cubic palladium-platinum hollow nanocage catalyzing D-glucose in the absence of light; B is the linear relationship between the absorbance change value and the D-glucose concentration under right-handed circularly polarized light irradiation. DETAILED DESCRIPTION

[0033] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] Unless otherwise specified, the technical means used in the following examples are all conventional means well known to those skilled in the art, and experimental methods without specific conditions are all conventional methods in the art.

[0035] Unless otherwise specified, the materials and reagents used in the following examples can be obtained from commercial sources.

[0036] A method for preparing chiral noble metal nanocages using penicillamine-induced synthesis, comprising the following steps:

[0037] (1) Synthesizing nanoscale palladium cubic or icosahedral solid nanoparticles as follows:

[0038] Polyvinyl pyrrolidone, ascorbic acid and potassium bromide are dissolved in deionized water (cubic) or diethylene glycol (icosahedron) to obtain a surfactant + reducing agent solution, wherein the concentration of polyvinyl pyrrolidone is 13-40 mg / mL, the concentration of ascorbic acid is 0-7.5 mg / mL, and the concentration of potassium bromide is 0-75 mg / mL; sodium tetrachloropalladate is then dissolved in deionized water (cubic) or diethylene glycol (icosahedron) to obtain a palladium metal salt precursor solution, wherein the concentration of sodium tetrachloropalladate is 15.5-18.7 mg / mL; subsequently, the surfactant + reducing agent solution and the palladium metal salt precursor solution are mixed under heating conditions to prepare palladium crystal seeds with cubic or icosahedral morphology; and after centrifugation, the supernatant is removed and the mixture is redispersed to obtain an ethylene glycol solution in which palladium nanocubes or icosahedral particles are dispersed.

[0039] (2) depositing platinum atoms on the palladium nanocubes or icosahedrons prepared above to form palladium-platinum cubic or icosahedral nanoparticles having a core-shell structure, as follows:

[0040] Polyvinyl pyrrolidone, ascorbic acid, and potassium bromide are dissolved in an ethylene glycol solution to obtain a surfactant+reducing agent solution, wherein the concentration of polyvinyl pyrrolidone is 12.5 mg / mL, the concentration of ascorbic acid is 6.25 mg / mL, and the concentration of potassium bromide is 10 mg / mL. The ethylene glycol solution in which the palladium nanocubes or icosahedral particles are dispersed is then added to the surfactant+reducing agent solution to obtain a reaction system solution. Sodium hexachloroplatinate is then dissolved in ethylene glycol to prepare a sodium hexachloroplatinate solution with a concentration of 0.58 to 1 mg / mL. The sodium hexachloroplatinate solution is gradually injected dropwise into the reaction system solution to react. The solution is centrifuged, the supernatant is removed, and the solution is redispersed to obtain an aqueous solution in which core-shell structured palladium-platinum nanocubes or icosahedral particles are dispersed.

[0041] (3) selectively etching the palladium core inside the palladium-platinum cubic or icosahedral nanoparticles prepared above using an aqueous solution system of ferric chloride, potassium bromide, and hydrochloric acid to obtain a hollow palladium-platinum nanocube or icosahedral framework, as follows:

[0042] The aqueous solution containing the core-shell structured palladium-platinum nanocubes or icosahedral particles prepared above is added to an aqueous system containing ferric chloride, potassium bromide, hydrochloric acid and polyvinyl pyrrolidone and mixed thoroughly. After continuous constant temperature reaction, the mixture is centrifuged, the supernatant is removed, and the mixture is redispersed to obtain an N,N-dimethylformamide solution containing hollow cubic or icosahedral palladium-platinum nanocages.

[0043] (4) Chiral D- / L-penicillamine molecules are used to induce gold atoms to deposit and grow on the palladium-platinum nanocube or icosahedral framework prepared above, thereby constructing a chiral palladium-platinum hollow nanocage structure, as follows:

[0044] Polyvinyl pyrrolidone, chloroauric acid, and D- / L-penicillamine are dissolved in an N,N-dimethylformamide solution, wherein the concentration of polyvinyl pyrrolidone is 70 mg / mL, the concentration of chloroauric acid is 0.3 mM, and the concentration of D- / L-penicillamine is 80 μM; then the N,N-dimethylformamide solution in which the cubic or icosahedral palladium-platinum nanocages prepared above are dispersed is added thereto, mixed and heated to react, and then centrifuged, the supernatant is removed, and redispersed to obtain an aqueous solution system in which chiral D- / L-configured cubic or icosahedral palladium-platinum hollow nanocages are dispersed, namely the chiral precious metal nanocage.

[0045] The chiral noble metal nanocage prepared by the above method comprises palladium, platinum and gold, and the molar ratio of the noble metals is (16-18):(24-28):(56-59). The chiral noble metal nanocage has a three-dimensional chiral morphology induced by the chiral molecule penicillamine, and the edge length is in the nanometer size.

[0046] Example 1 Preparation of D- / L-Configuration Cubic Palladium-Platinum Hollow Nanocages

[0047] A method for preparing chiral noble metal nanocages using penicillamine-induced synthesis, comprising the following steps:

[0048] 1. Preparation of Palladium Nanocubic Crystal Seeds

[0049] (1) Weigh 26 mg of polyvinylpyrrolidone (Mw ≈ 55,000), 15 mg of ascorbic acid, and 150 mg of potassium bromide and dissolve them in 2 mL of deionized water to obtain a colorless, transparent solution.

[0050] (2) Weigh 14 mg of sodium tetrachloropalladate and dissolve it in 0.75 mL of deionized water to obtain a reddish-brown solution.

[0051] (3) The colorless transparent solution was kept at 80°C in a 20 mL glass bottle for 10 min, and then the reddish-brown solution was added to the glass bottle and kept reacting at this temperature for 3 h. The color of the solution gradually changed from reddish-brown to black. After 3 h, the heating was stopped. After the reaction vessel cooled to room temperature, a mixed solution of 3 mL of deionized water and 37 mL of tetrahydrofuran was added to the black solution. The solution was then poured into a 50 mL centrifuge tube and centrifuged (9000 rpm, 10 min). The supernatant was poured out, and the black product at the bottom was dispersed in 3 mL of deionized water and centrifuged three times for washing. The obtained palladium nanocubic crystal seeds were then dispersed in 3 mL of ethylene glycol solution for later use.

[0052] 2. Preparation of cubic palladium-platinum core-shell nanoparticles

[0053] (1) Weigh 125 mg of polyvinylpyrrolidone (Mw ≈ 55,000), 62.5 mg of ascorbic acid, and 100 mg of potassium bromide and dissolve them in 7 mL of ethylene glycol solution to obtain a colorless, transparent solution.

[0054] (2) 5.8 mg of sodium hexachloroplatinate hexahydrate was weighed and dissolved in ethylene glycol at a concentration of 0.58 mg / mL to obtain an orange-yellow solution, which was then drawn into a syringe whose injection rate was controlled by a syringe pump.

[0055] (3) The colorless transparent solution was transferred to a 100 mL glass four-necked flask, and the palladium nanocubic crystal seed solution prepared above was added to the flask; the reaction vessel was heated by a heating jacket connected to a programmable temperature controller, starting from room temperature, and after 16 minutes, the mixed solution was heated to 110 ° C. and kept at this temperature for 20 minutes, and then after another 16 minutes, the mixed solution was heated to 195 ° C. (At this time, the injection pump was turned on and the orange-yellow solution was injected at a rate of 1 mL / h, and the injection was continued for 8 hours), and the reaction was maintained at this temperature for 9 hours, and the solution changed from light black to dark black. After 9 h, the heating was stopped. After the reaction vessel was cooled to room temperature, a mixed solution of 3 mL of deionized water and 37 mL of tetrahydrofuran was added to the solution, and then poured into a 50 mL centrifuge tube and centrifuged (9000 rpm, 10 min). The supernatant was poured out, and the black product at the bottom was dispersed in 2 mL of deionized water and poured into a centrifuge tube. The mixture was then centrifuged and washed three times. The obtained cubic palladium-platinum core-shell structured nanoparticles were then dispersed in 2 mL of deionized water for later use.

[0056] 3. Preparation of cubic palladium-platinum hollow nanocage structures

[0057] (1) Weigh 25 mg of polyvinylpyrrolidone (Mw ≈ 55,000), 150 mg of potassium bromide, and 25 mg of ferric chloride hexahydrate, add 150 μL of 12 M hydrochloric acid solution, dissolve in 3 mL of deionized water, and sonicate for 1–3 min to form a yellow solution.

[0058] (2) The yellow solution was transferred to a 50 mL glass bottle, and the cubic palladium-platinum core-shell structure nanoparticle solution prepared above was added to the glass bottle and reacted at 60 ° C for 3 h. After the reaction was completed, the reaction container was cooled to room temperature, 40 mL of anhydrous ethanol was added to the solution, and then poured into a 50 mL centrifuge tube and centrifuged (9000 rpm, 10 min). The supernatant was poured out, and the product was dispersed in 2 mL of deionized water, and then poured into a centrifuge tube. It was centrifuged and washed three times. The obtained cubic palladium-platinum hollow nanocages were then dispersed in 10 mL of N, N-dimethylformamide solution for use.

[0059] 4. Preparation of cubic chiral palladium platinum hollow nanocage catalyst

[0060] (1) Weigh 1.5 g of polyvinylpyrrolidone (Mw ≈ 55,000) and dissolve it in 16.25 mL of N,N-dimethylformamide solution. Add 0.3 mM aqueous chloroauric acid solution and 80 μM aqueous D- / L-penicillamine solution to obtain a light yellow solution.

[0061] (2) The light yellow solution was transferred to a 100 mL glass round-bottom flask, and 5 mL of the N,N-dimethylformamide solution of the cubic palladium-platinum hollow nanocage prepared above was added to the glass flask. The reaction vessel was heated by a heating mantle connected to a programmable temperature controller. Starting from room temperature, after 10 minutes, the mixed solution was heated to 80°C and kept at this temperature for 2 hours. After stopping heating, the reaction vessel was cooled to room temperature, deionized water was added to the solution, and centrifuged for three times (speed 9000 rpm, 10 minutes) to obtain D- / L-configuration cubic palladium-platinum hollow nanocage particles, which were then dispersed in 3 mL of deionized water for later use.

[0062] The D-cubic palladium platinum hollow nanocage prepared in this embodiment is as follows Figure 1 As shown in A and C, Figure 1 Figure A shows that the particles are hollow cubes with uniform size. Figure 1 C in the middle shows that the particles present a clockwise spiral structure; L-configuration cubic palladium platinum hollow nanocages such as Figure 1 As shown in B and D, Figure 1 Middle B shows that the particles are hollow cubes with uniform size. Figure 1 Middle D shows that the particles present a counterclockwise spiral structure.

[0063] The element distribution of the L-shaped cubic palladium platinum hollow nanocage prepared in this embodiment is as follows: Figure 2 As shown, the cubic particles contain three metal elements: palladium, platinum and gold, and the particle morphology is similar to Figure 1 The same as shown.

[0064] Example 2 Preparation of D- / L-Configuration Icosahedral PdPt Hollow Nanocages

[0065] 1. Preparation of palladium nano-icosahedral crystal seeds

[0066] (1) Weigh 80 mg of polyvinylpyrrolidone (Mw ≈ 55,000) and dissolve it in 2 mL of diethylene glycol. Then add 10 μL of 3 M hydrochloric acid aqueous solution to obtain a colorless, transparent solution.

[0067] (2) Weigh 15.5 mg of sodium tetrachloropalladate and dissolve it in 1 mL of diethylene glycol to obtain a reddish-brown solution.

[0068] (3) The colorless transparent solution was kept at 125°C in a 20 mL glass bottle for 10 min, and then the reddish-brown solution was added to the glass bottle and kept reacting at this temperature for 3 h. The color of the solution gradually changed from reddish-brown to black. After 3 h, the heating was stopped. After the reaction vessel cooled to room temperature, a mixed solution of 3 mL of deionized water and 37 mL of tetrahydrofuran was added to the black solution. The solution was then poured into a 50 mL centrifuge tube and centrifuged (9000 rpm, 10 min). The supernatant was poured out, and the black product at the bottom was dispersed in 3 mL of deionized water and centrifuged three times for washing. The obtained palladium nano-icosahedral crystal seeds were then dispersed in 3 mL of ethylene glycol solution for later use.

[0069] 2. Preparation of icosahedral palladium-platinum core-shell structured nanoparticles

[0070] (1) Weigh 125 mg of polyvinylpyrrolidone (Mw ≈ 55,000), 62.5 mg of ascorbic acid, and 100 mg of potassium bromide and dissolve them in 7 mL of ethylene glycol solution to obtain a colorless, transparent solution.

[0071] (2) Weigh 10 mg of sodium hexachloroplatinate hexahydrate and dissolve it in ethylene glycol at a concentration of 1 mg / mL to obtain an orange-yellow solution, which is then drawn into a syringe whose injection rate is controlled by a syringe pump.

[0072] (3) The colorless transparent solution was transferred to a 100 mL glass four-necked flask, and the palladium nano-icosahedral crystal seed solution prepared above was added to the flask; the reaction vessel was heated by a heating jacket connected to a programmable temperature controller, starting from room temperature, and after 16 minutes, the mixed solution was heated to 110 ° C. and kept at this temperature for 20 minutes, and then after another 16 minutes, the mixed solution was heated to 195 ° C. (At this time, the injection pump was turned on and the orange-yellow solution was injected at a rate of 1 mL / h, and the injection was continued for 8 hours), and the reaction was maintained at this temperature for 9 hours, and the solution changed from light black to dark black. After 9 h, the heating was stopped, and after the reaction container was cooled to room temperature, a mixed solution of 3 mL of deionized water and 37 mL of tetrahydrofuran was added to the solution, and then poured into a 50 mL centrifuge tube and centrifuged (9000 rpm, 10 min). The supernatant was poured out, and the black product at the bottom was dispersed in 2 mL of deionized water and poured into a centrifuge tube. The mixture was then centrifuged and washed three times. The obtained icosahedral palladium-platinum core-shell structured nanoparticles were then dispersed in 2 mL of deionized water for later use.

[0073] 3. Preparation of icosahedral palladium-platinum hollow nanocage structures

[0074] (1) Weigh 25 mg of polyvinylpyrrolidone (Mw ≈ 55,000), 150 mg of potassium bromide, and 25 mg of ferric chloride hexahydrate, add 150 μL of 12 M hydrochloric acid solution, dissolve in 3 mL of deionized water, and sonicate for 1–3 min to form a yellow solution.

[0075] (2) The yellow solution was transferred to a 50 mL glass bottle, and the icosahedral palladium-platinum core-shell structure nanoparticle solution prepared above was added to the glass bottle and reacted at 80°C for 3 h. After the reaction was completed and the reaction container was cooled to room temperature, 40 mL of anhydrous ethanol was added to the solution, and then poured into a 50 mL centrifuge tube and centrifuged (9000 rpm, 10 min). The supernatant was poured out, and the product was dispersed in 2 mL of deionized water, and then poured into a centrifuge tube and centrifuged three times. The obtained icosahedral palladium-platinum hollow nanocages were then dispersed in 5 mL of N,N-dimethylformamide for later use.

[0076] 4. Preparation of icosahedral chiral palladium platinum hollow nanocage catalyst

[0077] (1) Weigh 1.5 g of polyvinylpyrrolidone (Mw ≈ 55,000) and dissolve it in 16.25 mL of N,N-dimethylformamide solution. Add 0.3 mM aqueous chloroauric acid solution and 80 μM aqueous D / L-penicillamine solution to obtain a light yellow solution.

[0078] (2) The light yellow solution was transferred to a 100 mL glass round-bottom flask, and 5 mL of the N,N-dimethylformamide solution of the icosahedral palladium-platinum hollow nanocage prepared above was added to the glass flask; the reaction vessel was heated by a heating jacket connected to a programmable temperature controller, starting from room temperature, and after 10 minutes, the mixed solution was heated to 80°C, and the reaction was maintained at this temperature for 2 hours. After stopping heating, the reaction vessel was cooled to room temperature, deionized water was added to the solution, and centrifuged for three times (speed 9000 rpm, 10 minutes) to obtain D- / L-configuration icosahedral palladium-platinum hollow nanocage particles, which were dispersed in 3 mL of deionized water for later use.

[0079] The D-configuration icosahedral palladium platinum hollow nanocage prepared in this embodiment is as follows Figure 3 As shown in A and C, Figure 3 Figure A shows that the particles are hollow icosahedral in shape and uniform in size. Figure 3 C in the middle shows that the particles present a clockwise spiral structure; L-configuration icosahedral palladium platinum hollow nanocages such as Figure 3 As shown in B and D, Figure 3 Middle B shows that the particles are hollow icosahedral in shape and uniform in size. Figure 3 Middle D shows that the particles present a counterclockwise spiral structure.

[0080] The element distribution of the L-configuration icosahedral palladium platinum hollow nanocage prepared in this embodiment is as follows: Figure 4 As shown, the icosahedral particles contain three metal elements: palladium, platinum and gold, and the particle morphology is similar to Figure 3 The same as shown.

[0081] Example 3D-Glucose catalytic oxidation experiment

[0082] 1. Experimental steps

[0083] In a typical glucose oxidation experiment, 1 mL of 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (10 mM aqueous solution) was mixed with 1 mL of potassium persulfate (3.5 mM aqueous solution) and left in the dark for 12 hours to produce the 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid cation radical. To a sample vial containing 790 μL of 10 mM phosphate buffer solution (pH 7.4) were added 100 μL of the D-cubic palladium platinum hollow nanocage particle solution prepared in Example 1, 100 μL of D-glucose (1 M) solution, and 10 μL of the 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid cation radical solution. The reduction of 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid cation radical was measured by the change in absorbance at 734 nm, which is the catalytic effect of D-configuration cubic palladium platinum hollow nanocage particles on the oxidation of D-glucose.

[0084] On this basis, under the condition of right circularly polarized light (808nm, 1W / cm 2 ) irradiation conditions, the corresponding absorbance changes caused by the reaction system containing a series of glucose concentrations from 0 to 20 mM were tested.

[0085] 2. Experimental results

[0086] In the absence of light, the UV spectrum of D-glucose catalyzed by D-cubic palladium platinum hollow nanocages is as follows: Figure 5 As shown in Figure A, it can be seen that the absorbance at 734 nm decreased by 0.2 within 10 minutes, indicating that the 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid cation radical was reduced, which further indicates that the D-configured cubic palladium platinum hollow nanocage catalyzed the oxidation of D-configuration glucose.

[0087] Under right circularly polarized light irradiation, the linear relationship between the absorbance change and glucose concentration is as follows: Figure 5 As shown in B, it can be seen that the D-configuration cubic palladium platinum hollow nanocage catalyzes the oxidation of glucose at different concentrations, causing changes in absorbance. The detection sensitivity reaches 0.05 Abs / mM, and the minimum detection limit is 74 μM.

[0088] The embodiments described above are only some of the embodiments of the present invention, rather than all of the embodiments. The detailed description of the embodiments of the present invention is not intended to limit the scope of the invention as claimed, but merely represents selected embodiments of the present invention. The scope of protection of the present invention shall be based on the scope required by the claims. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making creative efforts shall fall within the scope of protection of the present invention.

Claims

1. A chiral noble metal nanocage synthesized by induction with penicillamine, characterized in that: The noble metals in the chiral noble metal nanocage are palladium, platinum and gold, and the molar ratio of the three is (16-18):(24-28):(56-59). The chiral noble metal nanocage has a three-dimensional chiral morphology induced by the chiral molecule of penicillamine, and the edge length is in the nanometer size.

2. The chiral noble metal nanocage synthesized by induction with penicillamine according to claim 1, characterized in that: The chiral noble metal nanocages include D-configuration cubic palladium platinum gold nanocages, L-configuration cubic palladium platinum gold nanocages, D-configuration icosahedral palladium platinum gold nanocages, and L-configuration icosahedral palladium platinum gold nanocages.

3. The method for preparing chiral noble metal nanocages synthesized by induction with penicillamine according to claim 1 or 2, characterized in that: The following steps are involved: Step 1) synthesizing nanoscale palladium cubic or icosahedral solid nanoparticles; step 2) depositing platinum atoms on the palladium nanocubes or icosahedrons prepared in step 1) to form palladium-platinum cubic or icosahedral nanoparticles with a core-shell structure; step 3) selectively etching the palladium core inside the palladium-platinum cubic or icosahedral nanoparticles prepared in step 2) using an aqueous solution system of ferric chloride, potassium bromide, and hydrochloric acid to obtain hollow palladium-platinum nanocubes or icosahedral frameworks; Step 4) chiral D- / L-penicillamine molecules are used to induce gold atoms to deposit and grow on the palladium-platinum nanocube or icosahedral framework prepared in step 3), thereby constructing a chiral palladium-platinum hollow nanocage structure.

4. The method for preparing chiral noble metal nanocages using penicillamine-induced synthesis according to claim 3, characterized in that: The specific steps of step 1) are as follows: dissolving polyvinyl pyrrolidone, ascorbic acid and potassium bromide in a solvent to obtain a surfactant + reducing agent solution, wherein the concentration of polyvinyl pyrrolidone is 13-40 mg / mL, the concentration of ascorbic acid is 0-7.5 mg / mL, and the concentration of potassium bromide is 0-75 mg / mL; then dissolving sodium tetrachloropalladate in the solvent to obtain a palladium metal salt precursor solution, wherein the concentration of sodium tetrachloropalladate is 15.5-18.7 mg / mL; then, mixing the surfactant + reducing agent solution and the palladium metal salt precursor solution under heating conditions to prepare palladium crystal seeds with cubic or icosahedral morphology; and centrifuging, removing the supernatant, and redispersing to obtain an ethylene glycol solution in which palladium nanocubes or icosahedral particles are dispersed.

5. The method for preparing chiral noble metal nanocages using penicillamine-induced synthesis according to claim 4, characterized in that: When the chiral noble metal nanocage is a cube, the solvent is deionized water; when the chiral noble metal nanocage is an icosahedron, the solvent is diethylene glycol.

6. The method for preparing chiral noble metal nanocages using penicillamine-induced synthesis according to claim 4, characterized in that: The specific steps of step 2) are as follows: dissolving polyvinyl pyrrolidone, ascorbic acid, and potassium bromide in an ethylene glycol solution to obtain a surfactant + reducing agent solution, wherein the concentration of polyvinyl pyrrolidone is 12.5 mg / mL, the concentration of ascorbic acid is 6.25 mg / mL, and the concentration of potassium bromide is 10 mg / mL; then adding the ethylene glycol solution in which the palladium nanocubes or icosahedral particles prepared in step 1) are dispersed to the surfactant + reducing agent solution to obtain a reaction system solution; then dissolving sodium hexachloroplatinate in ethylene glycol to prepare a sodium hexachloroplatinate solution with a concentration of 0.58 to 1 mg / mL, gradually injecting the sodium hexachloroplatinate solution dropwise into the reaction system solution to react, centrifuging, removing the supernatant, and redispersing to obtain an aqueous solution in which core-shell structured palladium-platinum nanocubes or icosahedral particles are dispersed.

7. The method for preparing chiral noble metal nanocages using penicillamine-induced synthesis according to claim 6, characterized in that: The specific steps of step 3) are as follows: adding the aqueous solution containing the core-shell structured palladium-platinum nanocubes or icosahedral particles prepared in step 2) to an aqueous system containing ferric chloride, potassium bromide, hydrochloric acid and polyvinyl pyrrolidone and mixing thoroughly, continuing the reaction at a constant temperature, centrifuging, removing the supernatant, and redispersing to obtain an N,N-dimethylformamide solution in which hollow cubic or icosahedral palladium-platinum nanocages are dispersed.

8. The method for preparing chiral noble metal nanocages using penicillamine-induced synthesis according to claim 7, characterized in that: The specific steps of step 4) are as follows: dissolving polyvinyl pyrrolidone, chloroauric acid, and D- / L-penicillamine in an N,N-dimethylformamide solution, wherein the concentration of polyvinyl pyrrolidone is 70 mg / mL, the concentration of chloroauric acid is 0.3 mM, and the concentration of D- / L-penicillamine is 80 μM; then adding the N,N-dimethylformamide solution dispersed with cubic or icosahedral palladium-platinum nanocages prepared in step 3) thereto, mixing and heating to react, then centrifuging, removing the supernatant, and redispersing to obtain an aqueous solution system dispersed with chiral D- / L-configuration cubic or icosahedral palladium-platinum hollow nanocages.

9. Use of the chiral noble metal nanocage according to claim 1 or 2, or the chiral noble metal nanocage prepared by the preparation method according to any one of claims 3 to 8, in glucose detection.

10. The use according to claim 9, characterized in that The chiral noble metal nanocage is used as a glucose functional mimic enzyme catalyst.

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