A Zn-K-MOF porous material and its synthesis method and application

Abstract

The present invention discloses a Zn-K-MOF porous material and a synthesis method and application thereof. The molecular formula of Zn-K-MOF is C 74 H 30 K3N2O 13 Zn; Zn-K-MOF is a metal organic framework material composed of Zn and K ions as nodes and 4,4'-(9,10-anthracenediyldi-1,1-ethylenediyl)bis-benzoic acid ligands as pillars; the Zn-K-MOF porous material provided by the present invention is simple to prepare, and Zn-K-MOF is used to detect amino acids in the environment, has good selectivity for Arg and Lys, and can achieve specific recognition and detection of Arg and Lys.

Description

Technical Field

[0001] The present invention belongs to the technical field of metal organic framework material preparation, and in particular relates to a Zn-K-MOF porous material and a synthesis method and application thereof. Background Art

[0002] For the human body, arginine (Arg) is an alkaline essential amino acid that can catalyze the ornithine cycle and promote the formation of urea. In addition, Arg is also an essential amino acid for maintaining the growth and development of infants and young children. Lysine (Lys) is one of the essential amino acids for humans and mammals, and it cannot be synthesized by itself and must be obtained from food. Lys has positive physiological significance in promoting human growth and development and enhancing the body's immunity. It is of great significance to the human body. Traditional methods for detecting Arg and Lys, such as gas chromatography and Raman spectroscopy, have high accuracy and stability, but have inconveniences such as complex operation, high price, and high usage requirements.

[0003] Therefore, it is urgent to provide an efficient and simple method for detecting Lys and Arg. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. To this end, the Zn-K-MOF porous material provided by the present invention is simple to prepare, and Zn-K-MOF is used to detect amino acids in the environment, and has good selectivity for Arg and Lys, and can achieve specific recognition and detection of Arg and Lys.

[0005] The second aspect of the present invention provides a method for preparing the Zn-K-MOF porous material.

[0006] The third aspect of the present invention proposes an application of the Zn-K-MOF porous material in amino acid detection.

[0007] According to a Zn-K-MOF porous material of the first embodiment of the present invention, the molecular formula of the Zn-K-MOF is C 74 H 30 K3N2O 13 Zn; the Zn-K-MOF is a metal organic framework material composed of Zn and K ions as nodes and 4,4'-(9,10-anthracenediyldi-1,1-ethylenediyl)bis-benzoic acid ligands as pillars.

[0008] The embodiments according to the first aspect of the present invention have at least the following beneficial effects:

[0009] The complex of the Zn-K-MOF porous material provided by the present invention has good stability, is easy to preserve, has good selectivity for Arg and Lys, can realize specific recognition and detection of Arg and Lys, and has simple and convenient detection operation and high sensitivity.

[0010] According to some embodiments of the present invention, the weight percentages of the components in the Zn-K-MOF porous material are carbon (66.11% to 67.32%), hydrogen (2.05% to 2.47%), potassium (2.02% to 3.14%), nitrogen (1.83% to 2.36%), oxygen (14.02% to 16.13%), and zinc (4.60% to 5.09%).

[0011] According to some embodiments of the present invention, the molar mass of the Zn—K-MOF porous material is M=1337.69 g / mol.

[0012] According to some embodiments of the present invention, the monoclinic system has unit cell parameters: a=45.116(2), Dc=1.410g cm -3 ,F 000 =2716.0, T=296(2)K, 2θ=54.98°, Z=4.

[0013] According to a second aspect of the present invention, a method for preparing the Zn-K-MOF porous material comprises: dispersing a zinc source, a potassium source, and a 4,4'-(9,10-anthracenediyldi-1,1-ethylenediyl)bis-benzoic acid ligand and then reacting them.

[0014] The embodiments according to the second aspect of the present invention have at least the following beneficial effects:

[0015] The Zn-K-MOF porous material single crystal prepared by the preparation method of the present invention has the advantages of good crystal shape, high yield, good thermal stability and the like.

[0016] According to some embodiments of the present invention, the zinc source includes zinc nitrate and zinc sulfate.

[0017] According to some embodiments of the invention, the potassium source comprises potassium acetate.

[0018] Acetic acid or acetate ion is a commonly used regulator in the hydrothermal / solvent synthesis of metal organic framework materials, which can adjust the crystal size and yield of the synthesized Zn-K-MOF. Therefore, the quality and yield of Zn-K-MOF prepared with potassium acetate as the potassium source are higher than those of other inorganic potassium sources, such as potassium nitrate and potassium sulfate.

[0019] According to some embodiments of the present invention, the molar ratio of the zinc source, the potassium source and the 4,4′-(9,10-anthracenediyldi-1,1-ethylenediyl)bis-benzoic acid is 1-1.1:2-2.3:60-63.

[0020] According to some embodiments of the invention, the dispersing process comprises vibration.

[0021] According to some embodiments of the invention, the vibration comprises ultrasonic vibration.

[0022] According to some embodiments of the present invention, the ultrasonic vibration duration is 15 to 20 minutes.

[0023] According to some embodiments of the present invention, the reaction container comprises a polytetrafluoroethylene reactor.

[0024] According to some embodiments of the present invention, the reaction system of the reaction further includes a solvent.

[0025] According to some embodiments of the present invention, the solvent includes N,N-dimethylacetamide or N,N-dimethylformamide.

[0026] According to some embodiments of the present invention, the reaction temperature is 100-120°C.

[0027] According to some embodiments of the present invention, the reaction time is 2 to 3 days.

[0028] According to some embodiments of the present invention, the reaction further includes washing and drying.

[0029] According to some embodiments of the present invention, the washing solvent includes at least one of N,N-dimethylacetamide, anhydrous ethanol and deionized water.

[0030] In the present invention, washing is performed until the washing liquid obtained by washing is colorless, which can ensure that the impurities on the surface of the crystal are washed away to obtain cubic orange crystals. Calculated based on the ligand, the final product yield is 80%.

[0031] According to some embodiments of the present invention, after the reaction is completed, cooling is also included before washing.

[0032] According to some embodiments of the present invention, the cooling rate is 5-6°C / h.

[0033] According to some embodiments of the present invention, after the reaction is completed, the temperature after cooling is room temperature.

[0034] According to the third aspect of the present invention, a Zn-K-MOF porous material is used in amino acid detection.

[0035] According to some embodiments of the invention, the amino acids include arginine and lysine.

[0036] According to some embodiments of the present invention, the minimum detection limit of the Zn-K-MOF porous material in arginine detection is 1.397×10 -4 M.

[0037] According to some embodiments of the present invention, the enhancement constant of arginine on the single crystal of the Zn-K-MOF porous material is 3.08×10 4 .

[0038] According to some embodiments of the present invention, the minimum detection limit of the Zn-K-MOF porous material in lysine detection is 1.502×10 -4 M.

[0039] According to some embodiments of the present invention, the enhancement constant of lysine on the single crystal of the Zn-K-MOF porous material is 2.636×10 4 .

[0040] The invention provides a Zn-K-MOF porous material complex with good stability, good preservation, resistance to high-temperature burning at 230°C, environmentally friendly and pollution-free, non-toxic to the human body, simple preparation process, high material yield, and the Zn-K-MOF porous material is used to detect amino acids in the environment, and two important amino acids can be effectively detected; the complex has good selectivity for Arg and Lys, and can realize specific recognition and detection of Arg and Lys; the detection operation is simple and convenient, the sensitivity is high, and the complex has high practicality.

[0041] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0043] Figure 1 A minimum asymmetric unit of the Zn-K-MOF prepared in Example 1;

[0044] Figure 2 is the structural formula of the 4,4'-(9,10-anthracenediyldi-1,1-ethylenediyl)bis-benzoic acid ligand of Example 1;

[0045] Figure 3 NMR of the synthesized 4,4'-(9,10-anthracenediyldi-1,1-ethylenediyl)bis-benzoic acid ligand;

[0046] Figure 4 is the XRD pattern of Zn-K-MOF of Example 1;

[0047] Figure 5 is the infrared spectrum of Zn-K-MOF of Example 1;

[0048] Figure 6 This is the thermogravimetric analysis diagram of Zn-K-MOF of Example 1;

[0049] Figure 7 15 μl of each amino acid (0.001 mol / L) was titrated into 3 ml (10 -4 M) Post-fluorescence quenching spectrum;

[0050] Figure 8 This is a sensitivity test spectrum of the complex of Example 1 after adding other ions and then adding Arg;

[0051] Fig. 9 This is a sensitivity test spectrum of the complex of Example 1 to Args;

[0052] Fig.10 The concentration of the complex in Example 1 is 10 -4 Linear fitting diagram of SV titrated with Arg at 400 M;

[0053] Fig.11 15 μl of each amino acid (0.001 mol / L) was titrated into 3 ml (10 - 4 M) Post-fluorescence quenching spectrum;

[0054] Fig.12 This is a sensitivity test spectrum of the complex of Example 1 after adding other ions and then adding Lys;

[0055] Fig.13 This is a spectrum diagram of the sensitivity test of the complex of Example 1 to Lys;

[0056] Fig.14 The concentration of the complex in Example 1 is 10 -4 Linear fitting diagram of SV titrated with Lys at M; DETAILED DESCRIPTION

[0057] The following will be combined with the embodiments to clearly and completely describe the concept of the present invention and the technical effects produced, so as to fully understand the purpose, characteristics and effects of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without paying creative labor all belong to the scope of protection of the present invention. The raw materials of the present invention are all commercially available.

[0058] Example 1

[0059] The preparation method of Zn-K-MOF provided in this embodiment is as follows:

[0060] (1) A mixture of zinc nitrate (0.05 mmol), potassium acetate (0.63 mmol), 4,4'-(9,10-anthracenediyldi-1,1-ethylenediyl)bis-benzoic acid (0.01 mmol) and 3 ml of N,N-dimethylacetamide was placed in a polytetrafluoroethylene reactor and subjected to ultrasonic vibration for 15-20 minutes;

[0061] (2) The reactor was placed in an oven at 100°C and heated for 2 days, and then cooled to room temperature at a rate of 5°C / h;

[0062] (3) The product was taken out and washed with N,N-dimethylacetamide, anhydrous ethanol, and deionized water in turn and air-dried to obtain yellow block-like transparent crystals. The yield was calculated based on the ligand to be 80%.

[0063] The structural formula of 4,4'-(9,10-anthracenediyldi-1,1-ethylenediyl)bis-benzoic acid is as follows Figure 2 As shown;

[0064] The H NMR spectrum of 4,4'-(9,10-anthracenediyldi-1,1-ethylenediyl)bis-benzoic acid is as follows Figure 3 As shown;

[0065] The H NMR spectrum of 4,4'-(9,10-anthracenediyldi-1,1-ethylenediyl)bis-benzoic acid ligand was measured at room temperature. The quartet peaks at chemical shifts of 7.80ppm and 8.66ppm correspond to hydrogens at positions 1, 4, 5, and 8 on the anthracene ring, and the quartet peak at 8.66ppm corresponds to hydrogens at positions 2, 3, 6, and 7 on the anthracene ring; the doublet peaks at chemical shifts of 7.99ppm and 8.08ppm correspond to two groups of hydrogens on the benzene rings on both sides. Since water in the solvent interacts with carboxyl hydrogens, the two carboxyl hydrogens are not obvious in low field. The chemical shift, splitting, and integrated area of ​​the peaks in the overall spectrum are consistent with the standard spectrum, and there are basically no impurity peaks, indicating that the ligand has a high purity.

[0066] The crystal structure, XRD and infrared spectrum of the Zn-K-MOF of the present invention are as follows: Figure 1 , Figure 4 , Figure 5 As shown;

[0067] Figure 4 It shows that the positions of all peaks in the experimental data of Zn-K-MOF are basically consistent with the positions of all peaks in the simulation (PXRD) pattern generated by the corresponding powder X-ray diffraction, which clearly shows that the Zn-K-MOF sample has a high purity.

[0068] Thermal stability is an important parameter of the complex. In order to study the thermal stability of the Zn-K-MOF, a thermogravimetric test was performed on it. Under nitrogen protection, the temperature was raised from 30°C to 800°C at a rate of 10°C / min. Figure 6 As shown, the TG curve shows that the first step of weight loss of the complex is from 140°C to 230°C, which is attributed to the release of free solvent molecules H2O; the second step of weight loss starts after 230°C, which is attributed to the collapse of the complex structure; indicating that the complex has good thermal stability.

[0069] Test Example 1

[0070] In this test example, deionized water was used to prepare aqueous solutions of various amino acids with a concentration of 0.01 mol / L, including 20 common amino acid aqueous solutions such as cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, and histidine.

[0071] 15 μl of the above-mentioned different amino acid solutions were added to the Zn-K-MOF fluorescent probe solution to detect the effects of different amino acids on the fluorescent signal. The results are as follows: Figure 7 As shown in Figure 11, only Arg and Lys significantly enhanced the fluorescence intensity, and other amino acids had almost no effect on the intensity of the fluorescent probe, indicating that the Zn-K-MOF fluorescent probe has good selectivity for Arg and Lys and can achieve specific recognition and detection of Arg and Lys.

[0072] 15 μl of different amino acid solutions were added to the Zn-K-MOF fluorescent probe solution to detect the effects of different amino acids on the fluorescent signal. The results are as follows: Figure 7 ,11, after adding Arg and Lys to the Zn-K-MOF suspension with various amino acids, the fluorescence intensity is significantly enhanced, as shown in Figure 8 ,12, which shows that Zn-K-MOF is not interfered by other amino acids when recognizing Arg and Lys.

[0073] Fig. 9 , 13 are the fluorescence titration spectra of Zn-K-MOF to Arg and Lys, respectively. Fig. 9From top to bottom, the sequence is 10μl, 9μl, 8μl, 7μl, 6μl, 5μl, 4μl, 3μl, 2μl, and 1μl of Arg. Fig.13 In the figure, from top to bottom, there are 10μl, 9μl, 8μl, 7μl, 6μl, 5μl, 4μl, 3μl, 2μl, and 1μl of Lys. As the volume of 0.01mol / L Arg and Lys added increases, the fluorescence intensity gradually increases. When more than 10μl of Arg and Lys are added, the fluorescence intensity is significantly enhanced.

[0074] Fig.10 , 14 are the linear fitting curves of SV of Zn-K-MOF for Arg and Lys respectively. The fluorescence enhancement efficiency was studied using the Stern-Volmer (SV) equation: I0 / I=1-Ksv[C], where [C] represents the concentration of Arg and Lys. From the figure, we can get the enhancement constants K SV 3.08×10 4 , 2.636×10 4 . Using the limit detection formula LOD = 3δ / K SV The detection limits for Arg and Lys were found to be 1.397×10 -4 M, 1.502×10 -4 M.

[0075] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A Zn-K-MOF porous material, characterized in that: The molecular formula of the Zn-K-MOF is C 74 H 30 K3N2O 13 Zn; The Zn-K-MOF porous material is a metal organic framework material composed of Zn and K ions as nodes and 4,4'-(9,10-anthracenediyldi-1,1-ethylenediyl)bis-benzoic acid ligands as pillars.

2. A method for preparing the Zn-K-MOF porous material according to claim 1, characterized in that: include: The zinc source, the potassium source and the 4,4'-(9,10-anthracenediyldi-1,1-ethylenediyl)bis-benzoic acid ligand are dispersed and reacted.

3. The preparation method according to claim 2, characterized in that: The zinc source includes zinc nitrate; the potassium source includes potassium acetate.

4. The preparation method according to claim 2, characterized in that: The molar ratio of the zinc source, the potassium source and the 4,4'-(9,10-anthracenediyldi-1,1-ethylenediyl)bis-benzoic acid is 1-1.1:2-2.3:60-63.

5. The preparation method according to claim 2, characterized in that: The dispersion process includes vibration; the vibration includes ultrasonic vibration; the duration of the ultrasonic vibration is 15 to 20 minutes.

6. The preparation method according to claim 2, characterized in that: The reaction further includes washing and drying.

7. The preparation method according to claim 6, characterized in that: The washing solvent includes at least one of N,N-dimethylacetamide, anhydrous ethanol and deionized water.

8. Use of the Zn-K-MOF porous material according to any one of claims 1 to 7 in the detection of arginine and lysine for non-diagnostic purposes.

9. The use according to claim 8, characterized in that: The minimum detection limit of the Zn-K-MOF porous material in arginine detection is 1.397×10 -4 M; The minimum detection limit of the Zn-K-MOF porous material in lysine detection is 1.502×10 -4 M.

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