Chiral iron-based nanowires and methods of making the same
By preparing chiral iron-based nanowires through reaction in alkaline aqueous solution, the problem of poor circular dichroism symmetry in the ultraviolet and visible light regions of chiral iron-based nanomaterials in the prior art has been solved. This method enables the preparation of nanowires with uniform morphology that are easy to mass-produce and is suitable for the study of enantiomeric chiral nanomaterials and chiral small molecules.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- DALIAN INSTITUTE OF CHEMICAL PHYSICS CHINESE ACADEMY OF SCIENCES
- Filing Date
- 2024-11-27
- Publication Date
- 2026-05-29
Smart Images
Figure CN122099347A_ABST
Abstract
Description
Technical Field
[0001] This application relates to a chiral iron-based nanowire and its preparation method, belonging to the field of nanomaterial synthesis technology. Background Technology
[0002] Chirality refers to the mirror symmetry of molecules in space, a property prevalent in nature, especially in biochemistry. Different stereochemical forms of chiral molecules can lead to differences in their functions within organisms; for example, left-handed and right-handed amino acids often exhibit drastically different biological activities. Naturally occurring organisms are primarily composed of left-handed amino acids and right-handed sugars, and this selective chirality may have played a crucial role in the evolution of life. Furthermore, the chirality of drugs is also vital; some chiral isomers of drugs may be effective, while others may cause side effects. Therefore, in-depth research into chirality not only reveals fundamental characteristics of life but also provides an important foundation for scientific research and pharmaceutical development.
[0003] The study of chiral nanomaterials is of significant value in materials science, chemistry, and biomedicine. First, the unique stereochemical properties of chiral nanomaterials endow them with specific optical, electronic, and catalytic properties, making them highly promising for applications in optoelectronic devices, sensors, and catalysts. Second, the advantages of these materials in terms of biocompatibility and selectivity have garnered widespread attention in drug delivery and targeted therapy. By modulating the chirality of nanomaterials, the recognition and binding of specific molecules in vivo can be achieved, thereby improving therapeutic efficacy and reducing side effects. Furthermore, chiral nanomaterials exhibit high selectivity in catalytic reactions, promoting specific reaction pathways and enhancing reaction efficiency. Therefore, the study of chiral nanomaterials not only advances basic science but also opens up broad prospects for the development of novel applications.
[0004] The significance of iron-based nanomaterials lies in their wide range of applications in catalysis, energy storage, and environmental remediation. Due to the abundance and low cost of iron, these materials offer excellent economic benefits and sustainability. Iron-based nanomaterials exhibit superior activity and selectivity in catalytic reactions, particularly in oxygen reduction reactions and the degradation of environmental pollutants. Furthermore, as electrode materials in batteries and supercapacitors, they can improve energy density and cycle stability. The magnetic properties of iron-based nanomaterials also make them valuable for applications in bioimaging and magnetic separation technologies. Summary of the Invention
[0005] To address the problem in existing technologies for preparing chiral iron-based nanomaterials that struggle to achieve good circular dichroism spectral symmetry in both the ultraviolet and visible light regions, this application proposes a technique for preparing chiral nanowires using amino acid induction. The synthetic method employed is simple, the product has a uniform morphology, and it is easy to achieve large-scale preparation. The prepared chiral iron-based nanowires exhibit symmetrical circular dichroism optical response.
[0006] The technical solution adopted in this application is as follows:
[0007] According to a first aspect of this application, a method for preparing chiral iron-based nanowires is provided, comprising the following steps:
[0008] The chiral iron-based nanowires are obtained by reacting an alkaline aqueous solution containing an iron source, a chiral ligand, a polyol solvent, a base, and an amine reducing agent.
[0009] The chiral ligand is selected from L-cysteine and / or D-cysteine.
[0010] Optionally, the preparation method specifically includes the following steps:
[0011] An aqueous solution of an iron source, an aqueous solution of a chiral ligand, and an alkaline solution are added to a polyol, and then an aqueous solution of an amine reducing agent is added to obtain an alkaline aqueous solution of the mixture. The reaction is carried out to obtain the chiral iron-based nanowires.
[0012] The chiral ligand is selected from L-cysteine and / or D-cysteine.
[0013] Optionally, the polyol solvent is selected from at least one of ethylene glycol and glycerol.
[0014] Optionally, the iron source is selected from at least one of ferric chloride, ferric nitrate, and ferric sulfate.
[0015] Optionally, the alkali is selected from at least one of sodium hydroxide, potassium hydroxide, sodium bicarbonate, and sodium carbonate.
[0016] Optionally, the amine reducing agent is selected from at least one of hydrazine hydrate, ammonia, hydroxylamine hydrochloride, and ethylenediamine.
[0017] Optionally, the concentration of the iron source aqueous solution is 30–60 mg / mL.
[0018] Optionally, the concentration of the iron source aqueous solution is selected from any value of 30 mg / mL, 40 mg / mL, 50 mg / mL, 60 mg / mL, or a range between any two of the above.
[0019] Optionally, the concentration of the chiral ligand aqueous solution is 20–50 mg / mL.
[0020] Optionally, the concentration of the chiral ligand aqueous solution is selected from any value of 20 mg / mL, 30 mg / mL, 40 mg / mL, 50 mg / mL, or a range between any two of the above.
[0021] Optionally, the concentration of the aqueous solution of the amine reducing agent is 5–10 mg / mL.
[0022] Optionally, the concentration of the aqueous amine reducing agent is selected from any value of 5 mg / mL, 6 mg / mL, 7 mg / mL, 8 mg / mL, 9 mg / mL, 10 mg / mL, or a range between any two of the above.
[0023] Optionally, the pH of the alkaline aqueous solution of the mixture is 8 to 10.
[0024] Optionally, the volume ratio of the iron source aqueous solution to the chiral ligand aqueous solution, the polyol solvent, and the amine reducing agent aqueous solution is (0.5-3):1:(5-10):(0.05-0.2).
[0025] Optionally, the volume ratio of the iron source aqueous solution to the chiral ligand aqueous solution is selected from any value of 0.5:1, 1:1, 2:1, 3:1 or a range between any two of the above.
[0026] Optionally, the reaction conditions include: being carried out under stirring conditions, with a stirring speed of 400–800 rpm / min, a reaction temperature of 40–80°C, and a reaction time of 2–6 h.
[0027] Optionally, the stirring speed is selected from any value among 400 rpm / min, 600 rpm / min, 800 rpm / min, or a range between any two of the above.
[0028] Optionally, the stirring reaction time is selected from any value of 4h, 5h, 6h, 7h, 8h or a range between any two of the above.
[0029] According to another aspect of this application, a chiral iron-based nanowire prepared by the above method is provided, wherein the characteristic peaks of the circular dichroism spectral signal of the chiral iron-based nanowire are 200-240 nm, 250-280 nm and 550-650 nm.
[0030] Optionally, the asymmetry factor g of the chiral iron-based nanowire is 0.0008-0.0016.
[0031] Optionally, the chiral iron-based nanowires have a diameter of 200–500 nm and a length greater than 50 μm.
[0032] The beneficial effects of this application include:
[0033] The chiral iron-based nanowires and their preparation method provided in this application are simple, produce products with uniform morphology, and are easy to prepare on a large scale. Both L and D configurations of the synthesized iron-based nanowires exhibit good circular dichroism spectral symmetry in the ultraviolet-visible region, which is of guiding significance for the preparation of enantiomeric chiral nanomaterials and the study of the synthesis of chiral nanomaterials induced by chiral small molecules. Attached Figure Description
[0034] Figure 1 The image shown is a scanning electron microscope (SEM) image of the iron-based nanowires synthesized by L-cysteine induced synthesis prepared in Example 1 of this application. The scale bar is 10.00 μm.
[0035] Figure 2 This is a scanning electron microscope (SEM) image of the iron-based nanowires synthesized by D-cystine in Example 1 of this application. The scale bar is 10.00 μm.
[0036] Figure 3 The circular dichroism spectra of the iron-based nanowires synthesized in Example 2 of this application induced by L-cysteine and the iron-based nanowires synthesized in accordance with D-cysteine are shown.
[0037] Figure 4 The images show the absorption spectra of the iron-based nanowires synthesized in accordance with L-cysteine and D-cysteine in Example 2 of this application.
[0038] Figure 5 The images show the g-factor spectra of the iron-based nanowires synthesized in Example 2 of this application, which were synthesized in accordance with L-cysteine and D-cysteine.
[0039] Figure 6 The images show the infrared spectra of the iron-based nanowires synthesized in accordance with L-cysteine and D-cysteine in Example 2 of this application.
[0040] Figure 7 The X-ray diffraction spectra of the iron-based nanowires synthesized by L-cysteine and D-cysteine in Example 2 of this application are shown. Detailed Implementation
[0041] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.
[0042] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.
[0043] Unless otherwise specified, all test methods are standard and all instrument settings are those recommended by the manufacturer.
[0044] Circular dichroism spectroscopy characterization: Circular dichroism spectroscopy was performed using a J1500 circular dichroism spectrometer from Japan Spectrophotometer Co., Ltd., with a detection wavelength range of 200-800 nm. Ultraviolet-visible absorption spectra were also collected simultaneously.
[0045] Scanning electron microscopy characterization: Scanning electron microscopy (SEM) images were taken using a JEOL JSM-7610Plus with an accelerating voltage of 5 kV.
[0046] Fourier transform infrared spectroscopy characterization: Fourier transform infrared spectra were measured using an INVENIO S infrared spectrometer from Bruker Instruments, Germany, with a detection wavelength range of 400-4000 nm.
[0047] X-ray diffraction spectroscopy characterization: X-ray diffraction spectra were measured using an Empyream X-ray diffraction spectrometer from Malvern Panaco Instruments Ltd., UK, with a detection angle of 5-90°.
[0048] As a specific implementation method, this application is achieved through the following technical solution:
[0049] A method for synthesizing chiral iron-based nanowires induced by chiral amino acid analogs includes the following steps: using ethylene glycol as a reaction solvent, using L-cysteine and D-cysteine as chiral ligands, using nonahydrate and ferric nitrate as iron sources, adding hydrazine hydrate as a reducing agent under alkaline reaction conditions, and inducing the generation of chiral iron-based nanowires under constant temperature and uniform stirring reaction conditions.
[0050] Furthermore, the synthesis method specifically includes the following steps:
[0051] S1. Adjust the alkalinity of the L-cysteine and D-cysteine chiral ligand solutions to ensure complete dissolution. Then, add the nonahydrate and ferric nitrate solutions, along with the L-cysteine and D-cysteine chiral ligands, sequentially to the ethylene glycol solvent. Hydrazine hydrate should be added as a reducing agent. Maintain a constant temperature and stir rapidly for 4-8 hours to obtain the chiral iron-based nanowire product.
[0052] S2. The obtained final product was purified by centrifugation to obtain the chiral iron-based nanowires.
[0053] Further, in step S1, when the nonahydrate and ferric nitrate solution react with L-cysteine and D-cysteine solutions respectively, an alkaline solution is added to L-cysteine and D-cysteine to adjust the pH to 8-10. The alkaline solution is sodium hydroxide solution, potassium hydroxide solution, sodium carbonate solution, and sodium bicarbonate solution.
[0054] In this invention, during specific operation, aqueous solutions of nonahydrate and ferric nitrate are prepared at room temperature. Then, aqueous solutions of L-cysteine and D-cysteine are prepared separately. The pH of the L-cysteine or D-cysteine solution is adjusted to 8-10 using sodium hydroxide solution to ensure complete dissolution. The prepared nonahydrate and ferric nitrate solutions and the L-cysteine or D-cysteine solutions are sequentially added to an Erlenmeyer flask containing ethylene glycol. Hydrazine hydrate reducing agent is then added, and the reaction is carried out under constant temperature of 40°C with stirring. The final color of the solution is observed to be brownish-yellow.
[0055] Example 1: Preparation of chiral iron-based nanowires induced by chiral cystine
[0056] (1) Weigh 400 mg of nonahydrate and ferric nitrate solid powder and add them to 10 mL of ultrapure water to dissolve. Then prepare 100 mM L-cystine and D-cystine aqueous solutions respectively. Weigh 240 mg of the two chiral ligands and dissolve them in 8 mL of water respectively. Adjust the pH of the chiral ligand solution to about 8-10 with 1 M sodium hydroxide solution. Then add 0.75 mL of the prepared nonahydrate and ferric nitrate solution and 1 mL of L-cystine or D-cystine solution to an Erlenmeyer flask containing 8.25 mL of ethylene glycol. Add 0.1 mL of hydrazine hydrate solution and stir magnetically at 40 °C for 4 h to obtain L-type chiral iron-based nanowires (labeled as Fe-L-cystine) and D-type chiral iron-based nanowires (labeled as Fe-D-cystine). The color of the solution turns brownish-yellow.
[0057] (2) Centrifugal purification: The obtained L-type and D-type chiral iron-based nanowires were separated by centrifugation. The centrifugation speed was 4000 rpm for 5 minutes. The supernatant was removed, and the precipitate was washed twice with ultrapure water to obtain L-type chiral iron-based nanowires and D-type chiral iron-based nanowires, respectively (the precipitate was resuspended in ultrapure water and could be used for circular dichroism spectroscopy and morphological characterization by scanning electron microscopy).
[0058] (3) Drying: The L-type and D-type chiral iron-based nanowire materials obtained by separation and purification are placed in a vacuum drying oven at 60℃ and dried to obtain L-type and D-type chiral iron-based nanowire solid powders (the solid powders can be used for Fourier transform infrared spectroscopy and X-ray diffraction spectroscopy characterization).
[0059] Test Example 1: Characterization Method of Chiral Iron-Based Nanowires Induced by Chiral Amino Acid Analogs
[0060] Scanning electron microscopy characterization:
[0061] The chiral iron-based nanowires obtained after centrifugal purification were resuspended in ultrapure water and diluted to a concentration of 0.5 mg / mL. 6 μL of each nanowire was dropped onto a silicon wafer surface and allowed to stand until the water completely evaporated. The morphology was observed under a 3-5 kV scanning electron microscope. (SEM image of L-type chiral iron-based nanowires synthesized with L-cysteine participation). Figure 1 Scanning electron microscope image of D-type chiral iron-based nanowires synthesized with the participation of D-cysteine. Figure 2 ), with a diameter of 200–500 nm and a length greater than 50 μm, from Figure 1 and Figure 2 It can be seen that L-cysteine and D-cysteine have similar diameters and lengths in the synthesized materials.
[0062] Circular dichroism spectral characterization:
[0063] The chiral iron-based nanowires obtained by centrifugation purification were resuspended in ultrapure water and diluted to 0.5 mg / mL. Using ultrapure water as the baseline background, the wavelength range was scanned from 200 to 800 nm at a scan rate of 1 s / nm. The circular dichroism and UV-Vis absorption spectra of the nanowires synthesized with the participation of L-cysteine and D-cysteine were obtained. Figure 3 and Figure 4 ),from Figure 3 It can be seen that the nanowires synthesized with the participation of L-cysteine and D-cysteine exhibit good symmetry in their circular dichroism (BDD) spectra, and the characteristic peaks are in the same position, showing obvious DCD characteristic peaks at wavelengths of 220 nm, 260 nm, and 600 nm, respectively. Furthermore, the DCD spectra of the materials synthesized with L-cysteine and D-cysteine are symmetrically distributed. Figure 4 The data shows that the material exhibits significant absorption at wavelengths of 250 nm, 400 nm, and 500 nm. Furthermore, the g-factor spectra of the chiral iron-based nanowires demonstrate good symmetry, with a maximum g-factor of 0.001. Figure 5 ).
[0064] Fourier transform infrared spectroscopy and X-ray electron diffraction spectroscopy characterization:
[0065] The powder obtained by vacuum drying of the chiral iron-based nanowires purified by centrifugation was used to determine the Fourier transform infrared spectrum. Figure 6 ) and X-ray electron diffraction spectroscopy ( Figure 7 ),from Figure 6 It can be seen that the characteristic peak of the carboxyl group in L-cystine is 1700 cm⁻¹ before and after the reaction. -1 Significant changes occurred, and it participated in the synthesis of chiral iron-based nanowires. Figure 7 Mid-X-ray electron diffraction spectroscopy indicates that the synthesized chiral iron-based nanowires have a specific crystalline structure.
[0066] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.
Claims
1. A method for preparing chiral iron-based nanowires, characterized in that, Includes the following steps: The chiral iron-based nanowires are obtained by reacting an alkaline aqueous solution containing an iron source, a chiral ligand, a polyol solvent, a base, and an amine reducing agent. The chiral ligand is selected from L-cysteine and / or D-cysteine.
2. The preparation method according to claim 1, characterized in that, The preparation method specifically includes the following steps: An aqueous solution of an iron source, an aqueous solution of a chiral ligand, and an alkaline solution are added to a polyol, and then an aqueous solution of an amine reducing agent is added to obtain an alkaline aqueous solution of the mixture. The reaction is carried out to obtain the chiral iron-based nanowires. The chiral ligand is selected from L-cysteine and / or D-cysteine.
3. The preparation method according to claim 2, characterized in that, The polyol solvent is selected from at least one of ethylene glycol and glycerol.
4. The preparation method according to claim 2, characterized in that, The iron source is selected from at least one of ferric chloride, ferric nitrate, and ferric sulfate.
5. The preparation method according to claim 2, characterized in that, The alkali is selected from at least one of sodium hydroxide, potassium hydroxide, sodium bicarbonate, and sodium carbonate.
6. The preparation method according to claim 2, characterized in that, The amine reducing agent is selected from at least one of hydrazine hydrate, ammonia, hydroxylamine hydrochloride, and ethylenediamine.
7. The preparation method according to claim 2, characterized in that, The concentration of the iron source aqueous solution is 30–60 mg / mL; Preferably, the concentration of the chiral ligand aqueous solution is 20–50 mg / mL; Preferably, the concentration of the aqueous solution of the amine reducing agent is 5–10 mg / mL; Preferably, the pH of the alkaline aqueous solution of the mixture is 8 to 10; Preferably, the volume ratio of the iron source aqueous solution to the chiral ligand aqueous solution, the polyol solvent, and the amine reducing agent aqueous solution is (0.5-3):1:(5-10):(0.05-0.2).
8. The preparation method according to claim 2, characterized in that, The reaction conditions include: being carried out under stirring conditions, with a stirring speed of 400–800 rpm / min, a reaction temperature of 40–80℃, and a reaction time of 2–6 h.
9. The chiral iron-based nanowires obtained by the preparation method according to any one of claims 1 to 8, characterized in that, The characteristic peaks of the circular dichroism spectral signal of the chiral iron-based nanowires are 200-240 nm, 250-280 nm and 550-650 nm. Preferably, the asymmetry factor g of the chiral iron-based nanowire is 0.0008-0.0016.
10. The chiral iron-based nanowire according to claim 9, characterized in that, The chiral iron-based nanowires have a diameter of 200–500 nm and a length greater than 50 μm.