Preparation method and application of metal organic framework based on silicon oxomolybdate modification

Abstract

The invention relates to the technical field of preparation methods of metal organic frameworks, and discloses a preparation method and application of a silicon oxomolybdate modified metal organic framework, zirconium chloride and terephthalic acid are respectively added into DMF, ultrasonic dissolution is performed, and after the two solutions are mixed, ultrasonic dissolution is performed again; transferring the obtained final product into a reaction kettle, and putting the reaction kettle into a drying oven for reaction; centrifuging the obtained final product, washing with a mixed solution of methanol and DMF (Dimethyl Formamide), and drying in a drying oven to obtain white UiO-66 powder; adding the obtained UiO-66 white powder into a silicomolybdic acid solution, and stirring; and centrifuging the obtained final product, discarding the supernatant, washing the precipitate with water, and drying in a drying oven to obtain SiMo12O40-coated UiO-66 light green powder, namely the metal organic framework based on silicon oxomolybdate modification. The silicomolybdic acid modified metal organic framework has remarkable advantages in the aspect of protein separation.

Description

Technical Field

[0001] The present invention relates to the technical field of metal organic framework preparation methods, and in particular to a metal organic framework preparation method based on silicomolybdate modification and application. Background Art

[0002] Metal-organic framework materials are three-dimensional structures composed of metal ions or metal clusters and organic ligands through coordination bonds. They have high porosity and adjustable surface properties, which enable them to interact efficiently with different types of target molecules. Especially when separating proteins, they can achieve specific adsorption according to the size, surface charge, hydrophilicity and other characteristics of proteins, thereby enriching low-abundance proteins in complex biological samples and reducing the interference of high-abundance proteins. Compared with traditional solid-phase extraction materials, metal-organic framework materials can improve the adsorption efficiency of proteins due to their ultra-large specific surface area and highly adjustable functional sites, and their stability and reusability are also superior. In recent years, the application of metal-organic framework materials in protein separation, enrichment and detection has made significant progress, providing new technical support for improving the sensitivity and accuracy of proteomics research and biomarker screening. In summary, we have developed a metal-organic framework composite material modified with silicomolybdic acid to improve the adsorption function of a single metal-organic framework. Summary of the invention

[0003] The purpose of the present invention is to provide a method for preparing a metal organic framework modified with molybdenum oxosilicic acid salt and its application, so as to solve the problems raised in the above background technology.

[0004] In order to solve the above technical problems, the present invention provides the following technical solution: a preparation method of a metal organic framework modified with silicomolybdate, comprising the following specific steps:

[0005] Step 1, adding zirconium chloride and terephthalic acid into DMF respectively, dissolving by ultrasonication, mixing the above two solutions, and dissolving by ultrasonication again;

[0006] Step 2: Transfer the final product obtained in step 1 to a reaction kettle and place it in an oven for reaction;

[0007] Step 3: After centrifuging the final product obtained in step 2, washing it with a mixed solution of methanol and DMF, and drying it in a drying oven to obtain UiO-66 white powder;

[0008] Step 4: Add the UiO-66 white powder obtained in step 3 to the silicomolybdic acid solution and stir;

[0009] Step 5: After centrifuging the final product obtained in step 4, the supernatant is discarded, the precipitate is washed with water, and placed in a drying oven to dry to obtain SiMo12 O 40 @UiO-66 light green powder, that is, a metal organic framework modified with molybdenum silicoacid was obtained.

[0010] According to the above technical solution, in step 1, 0.4 g of zirconium chloride is added to 45 ml of DMF, 0.28 g of terephthalic acid is added to 15 ml of DMF, the ultrasonic dissolution time is 30 min, and the ultrasonic dissolution time is again 10 min.

[0011] According to the above technical solution, the volume of the reactor in step 2 is 100 ml, the temperature in the oven is 100° C., and the reaction time is 25 h.

[0012] According to the above technical scheme, the volume ratio of methanol to DMF in step three is 4:1, the number of washings is 3 times, the temperature in the oven is 65° C., and the drying time is 5 hours.

[0013] According to the above technical scheme, the mass of UiO-66 white powder in step 4 is 60 mg, the concentration and volume of silicomolybdic acid solution are 2 mg / ml and 30 ml respectively, and the stirring temperature and time are room temperature and 24 h respectively.

[0014] According to the above technical solution, the number of water washings in step 5 is 4, the temperature in the drying oven is 65° C., and the drying time is 3 hours.

[0015] A SiMo 12 O 40 @UiO-66 is used to remove high-abundance proteins in plasma.

[0016] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0017] Silicomolybdic acid-modified metal organic frameworks have significant advantages in separating proteins. First, silicomolybdic acid is a material with high surface activity and good stability. It can improve the hydrophilicity and selectivity of MOFs by combining with metal organic frameworks. This modification can enhance the adsorption capacity of MOFs for protein molecules.

[0018] Compared with traditional separation methods such as affinity chromatography or liquid-liquid extraction, silicomolybdic acid-modified MOFs have higher separation efficiency and lower background interference. Silicomolybdic acid can not only improve the surface chemical properties of MOFs, but also increase the selective adsorption of target molecules through interaction with proteins, thereby achieving more precise separation. This allows silicomolybdic acid-modified MOFs to more effectively remove the interference of high-abundance proteins, enrich low-abundance proteins, and improve detection sensitivity when processing complex biological samples.

[0019] In addition, silicomolybdic acid-modified MOFs have high chemical and thermal stability, can maintain performance under harsh experimental conditions, and have adjustable structures that can be optimized for different types of proteins. These advantages make this new material a more efficient, stable and sensitive separation method in the fields of proteomics research and disease marker screening. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0021] Figure 1 It is the scanning electron microscope image and the transmission electron microscope image in the present invention;

[0022] Figure 2 It is the Fourier infrared spectrum diagram, Raman analysis result diagram, EDS analysis result diagram, and VSM analysis result diagram in the present invention;

[0023] Figure 3 The effect of pH value and ionic strength on protein adsorption efficiency in the present invention is shown in the figure;

[0024] Figure 4 The effect of adsorption time and adsorption temperature on adsorption efficiency in the present invention is shown in the figure;

[0025] Figure 5 The different types of eluents in the present invention have an effect on the adsorption of SiMo 12 O 40 @HSA recovery on UiO-66 and optimization of HSA eluent concentration;

[0026] Figure 6 It is a diagram of the SDS-PAGE analysis results in the present invention. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] See also Figure 1-6 , the present invention provides a technical solution:

[0029] A method for preparing a metal organic framework based on silicomolybdate modification comprises the following specific steps:

[0030] 0.4 g zirconium chloride and 0.28 g terephthalic acid were added to 45 ml and 15 ml DMF respectively, and ultrasonically dissolved for 30 min. After mixing the above two solutions, ultrasonically dissolve for 10 min, transfer to a 100 ml reactor, and react in an oven at 100 ° C for 25 h. After centrifugation, the obtained product was washed three times with a mixed solution of methanol: DMF = 4:1, and dried in a drying oven at 65 ° C for 5 h to obtain a white powder.

[0031] SiMo 12 O 40 Preparation of @UiO-66 composite materials

[0032] 60 mg of UiO-66 powder was added to 30 ml of 2 mg / ml silicomolybdic acid solution and stirred at room temperature for 24 h. The product was centrifuged and the supernatant was discarded. The precipitate was washed with water 4 times and dried in a drying oven at 65°C for 3 h to obtain a light green powder.

[0033] SiMo 12 O 40 @UiO-66 is used to remove high-abundance proteins in plasma.

[0034] Experimental materials:

[0035] IgG dry powder (IgG), cytochrome C, riboflavin binding protein (RBP); serum albumin; transferrin (TRF); pepsin (Pep);

[0036] Protein molecular weight standards (myosin, Mr 200.0 kDa; β-galactosidase, Mr 116.0 kDa; phosphatase b, Mr 97.2 kDa; bovine serum albumin, Mr 66.4 kDa; ovalbumin, Mr 44.3 kDa; carbonic anhydrase, Mr 29.0 kDa; trypsin inhibitor, Mr 20.1 kDa; lysozyme, Mr 14.3 kDa; aprotinin, Mr 6.5 kDa);

[0037] Coomassie Brilliant Blue G250, phosphoric acid (H3PO4); glacial acetic acid (CH3COOH), boric acid (H3BO3); sodium hydroxide (NaOH); sodium chloride (NaCl); all reagents were of analytical grade unless otherwise stated and were not pretreated before use. The experimental water was secondary deionized water (ddH2O, 18 MΩcm).

[0038] Experimental steps:

[0039] 60 mg of UiO-66 powder was added to 30 ml of 2 mg / ml silicomolybdic acid solution and stirred at room temperature for 24 h. The product was centrifuged and the supernatant was discarded. The precipitate was washed with water 4 times and dried in a drying oven at 65°C for 3 h to obtain a light green powder.

[0040] result:

[0041] SiMo 12 O 40 @UiO-66 scanning electron microscope (SEM), infrared spectrum (FT-IR), Raman spectrum (Raman), EDS spectrum diagram as shown Figure 1 , 2 As shown, Figure 1 UiO-66(A)SiMo 12 O 40 @UiO-66(B), Figure 2 UiO-66 and SiMo 12 O 40 Fourier transform infrared spectrum (A) and Raman analysis results (B) of @UiO-66; SiMo 12 O 40 @UiO-66EDS analysis results (C); UiO-66 and SiMo 12 O 40 @UiO-66 VSM analysis results (D) show that the nanoparticles with a size of about 120 nm are dispersed evenly, and larger particles are formed, which proves that SiMo 12 O 40 Successfully bonded to the surface of metal-organic framework materials.

[0042] Example 2 Protein adsorption and elution:

[0043] Experimental steps:

[0044] To investigate SiMo 12 O 40 @UiO-66 composite material adsorption performance on proteins, serum albumin (HSA), transferrin (TRF), immunoglobulin (IgG) and cytochrome C (Cyt-C), riboflavin binding protein (RBP), pepsin (Pep) were selected as model proteins. 12 O 40 @UiO-66 was added to a 1.5 mL centrifuge tube and mixed with 1 ml of 100 μg mL -1 The protein solution was mixed and shaken for 30 minutes. Centrifuged at 8000r for 5 minutes to separate the supernatant. 60μL of the supernatant was collected and the residual protein concentration in the solution was quantified by the absorption peak intensity of the protein solution stained with Coomassie Brilliant Blue at 595nm. The protein concentration before and after adsorption was calculated using the standard working curve. The adsorption efficiency of protein in the experiment was calculated by formula (1):

[0045]

[0046] Where: E 1is the adsorption efficiency of protein (%); C 0 is the original concentration of the protein prepared in the experiment (μg mL -1 );C 1 is the concentration of protein in the solution after adsorption (μgmL -1 ).

[0047] Collect the separated SiMo 12 O 40 @UiO-66, add 1 ml of 50 mM / L PBS (pH = 7.2) as eluent, shake for 30 minutes, and remove the adsorbed 12 O 40 HSA, TRF, and IgG on the surface of @UiO-66 were eluted. After centrifugation, the supernatant was taken to measure the absorption peak intensity at 595nm, and the elution efficiency was calculated based on the protein content in the eluate and the amount of protein adsorbed by the adsorbent. The elution rate of the protein in the experiment can be calculated by formula (2).

[0048]

[0049] Where E 2 is the elution rate of the protein, C 0 is the original concentration of the protein in the experiment, C 1 is the concentration of white in the solution after adsorption, C 2 is the protein concentration in the solution after elution.

[0050] Removal of high-abundance proteins in actual samples:

[0051] Take a certain volume of healthy serum and dilute it 300 times with BR solution with pH=5 and NaCl concentration of 700mmol / L. 12 O 40 @UiO-66, add 1ml diluted whole blood serum sample, shake for 30 minutes, remove the supernatant. Add 1ml, 50mM / L PBS (pH=7.2), shake for 30min, centrifuge, remove the supernatant, and obtain the purified high-abundance protein.

[0052] result:

[0053] Effects of pH and ionic strength on protein adsorption efficiency Figure 3 , The effect of pH value on the adsorption efficiency of HSA, TRF, IgG, Cytc, RBP, and Pep (A); protein solution: 100 μg mL -1 ,1ml;SiMo 12 O 40@UiO-66: 1 mg (A); Effect of NaCl concentration on the adsorption efficiency of HSA, TRF, IgG, Cytc, RBP, and Pep at pH 5.0 (B), and the effects of adsorption time and temperature on the adsorption efficiency. Figure 4 , the adsorption time during the process has an effect on SiMo 12 O 40 @The effect of HSA adsorption on UiO-66 (A); Under the condition of 25℃, the adsorption time has an effect on the adsorption of SiMo 12 O 40 @The effect of HSA adsorption on UiO-66 (B); SiMo 12 O 40 @UiO-66 adsorption isotherm of HSA (C)1 / q eq With 1 / C eq Protein solution: 125-275 μg mL -1 ,1mLSiMo 12 O 40 @UiO-66: 1mg; adsorption time: 30min, by Figure 4 It can be seen that with the increase of hemoglobin concentration, SiMo 12 O 40 @UiO-66's unit adsorption capacity for HSA gradually increased, indicating that SiMo 12 O 40 The adsorption behavior of HSA on UiO-66 is well correlated with the Langmuir isotherm, which indicates that the adsorption of HSA on the material is monolayer adsorption. Different types of eluents have a significant effect on the adsorption of HSA on SiMo 12 O 40 @UiO-66 Recovery of hemoglobin Figure 5 , the effect of different types of eluents on adsorption on SiMo 12 O 40 @Recycling of HSA on UiO-66 (A); SiMo 12 O 40 @UiO-66 optimizes HSA eluate concentration. Albumin solution: 100 μg mL -1 ,1ml,pH5.0;SiMo 12 O 40 @UiO-66: 1.0 mg; adsorption time: 30 min; eluent volume: 1 ml, SDS-PAGE analysis results see Figure 6 Lane 1: protein marker; Lane 2: healthy human serum diluted 300 times; Lane 3: SiMo 12 O 40@UiO-66 adsorption supernatant; Lane 4: supernatant after elution with 50mM / L PBS; Lane 5: albumin, transferrin and IgG standard sample mixture, protein bands appear at 75kDa, 66.4kDa, 50kDa and 25kDa, which are consistent with the bands of transferrin, albumin, IgG heavy chain and light chain, indicating that the use of SiMo 12 O 40 @UiO-66 was used as an adsorbent to separate and remove high-abundance proteins in blood samples.

[0054] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing a metal organic framework based on silicomolybdate modification, characterized in that: The specific steps include: Step 1, adding zirconium chloride and terephthalic acid into DMF respectively, dissolving by ultrasonication, mixing the above two solutions, and dissolving by ultrasonication again; Step 2: Transfer the final product obtained in step 1 to a reaction kettle and place it in an oven for reaction; Step 3: After centrifuging the final product obtained in step 2, washing it with a mixed solution of methanol and DMF, and drying it in a drying oven to obtain UiO-66 white powder; Step 4: Add the UiO-66 white powder obtained in step 3 to the silicomolybdic acid solution and stir; Step 5: After centrifuging the final product obtained in step 4, the supernatant is discarded, the precipitate is washed with water, and placed in a drying oven to dry to obtain SiMo 12 O 40 @UiO-66 light green powder, that is, a metal organic framework modified with molybdenum silicoacid was obtained.

2. The method for preparing a metal organic framework based on silicomolybdate modification according to claim 1, characterized in that: In step 1, 0.4 g of zirconium chloride is added to 45 ml of DMF, and 0.28 g of terephthalic acid is added to 15 ml of DMF. The ultrasonic dissolution time is 30 min, and the ultrasonic dissolution time is again 10 min.

3. The method for preparing a metal organic framework based on silicomolybdate modification according to claim 2, characterized in that: In step 2, the volume of the reactor is 100 ml, the temperature in the oven is 100° C., and the reaction time is 25 h.

4. The method for preparing a metal organic framework based on silicomolybdate modification according to claim 3, characterized in that: In step 3, the volume ratio of methanol to DMF is 4:1, the number of washings is 3 times, the temperature in the oven is 65° C., and the drying time is 5 h.

5. The method for preparing a metal organic framework modified with molybdenum oxosilicolate and its application according to claim 4, characterized in that: In step 4, the mass of UiO-66 white powder is 60 mg, the concentration and volume of silicomolybdic acid solution are 2 mg / ml and 30 ml, respectively, and the stirring temperature and time are room temperature and 24 h, respectively.

6. The method for preparing a metal organic framework modified with silicomolybdate and its application according to claim 5, characterized in that: In step 5, the number of water washings is 4, the temperature in the drying oven is 65° C., and the drying time is 3 h.

7. A method for preparing a metal organic framework based on silicomolybdate modification according to any one of claims 1 to 6 wherein SiMo 12 O 40 @UiO-66 is used to remove high-abundance proteins in plasma.

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