A type of NH 4+ Biotransformation scavenging materials and their preparation methods

Abstract

This invention relates to the field of biomedical technology, and provides an NH4 + Biotransformation scavenging materials and their preparation methods utilize glutamate dehydrogenase to decompose urea into NH4, which is generated by urease. + α-Ketoglutarate and nicotinamide adenine dinucleotide are converted into glutamate under the action of enzymes, thereby removing NH4, which is highly toxic to the human body. + Furthermore, MAF-7 material was synthesized by reacting zinc nitrate and 3-methyl-1,2,4-triazole in aqueous solution. Simultaneously, glutamate dehydrogenase was added during the synthesis process to immobilize the enzyme in situ onto MAF-7. This material can regenerate NH4+, a byproduct of peritoneal dialysis fluid regeneration in WAK. + It can effectively remove NH4 and also achieve long-term continuous removal. + This reduces the amount of adsorbent used and the size and weight of the device, further improving the urea treatment efficiency and solving the Na+ problem in the REDY system. + H + Risk of leakage.

Description

Technical Field

[0001] This invention relates to the field of biomedical technology, and more particularly to an NH 4+ Biotransformation scavenging materials and their preparation methods. Background Technology

[0002] Impaired kidney function leads to the accumulation of toxins in the body, such as urea, creatinine, and uric acid. This accumulation can further cause a range of kidney diseases, including kidney failure and uremia. Wearable artificial kidneys (WAKs), with their complete dialysis devices and processes, can achieve efficient and continuous removal of uremic toxins.

[0003] Currently, most systems meeting WAK requirements are circulating dialysis adsorbent systems (REDY) with filter cartridges. The toxin removal section of a REDY filter cartridge mainly consists of activated carbon, urease, and a zirconium oxide / zirconium phosphate ion exchanger. First, the peritoneal dialysis fluid passes through the activated carbon section, removing most of the non-urea organic compounds; then, urease decomposes urea into carbonates and NH4+. + Then, NH4+ is removed by a zirconium oxide-zirconium phosphate ion exchanger. + Exchange for Na + and H + This is done to remove urea.

[0004] Urea, also known as urea or carbamide, is a difficult-to-remove toxin. It is a white or colorless needle- or rod-shaped crystal with the chemical formula CO(NH2)2. It is a major nitrogenous waste product of metabolism in mammals, usually excreted through urine or sweat. As a form of ammonia detoxification in the human body, urea is highly water-soluble and is generally transported to the kidneys via the bloodstream and excreted in urine, accounting for approximately 90% of renal excretion. Its maximum daily production is approximately 240-470 mmol. However, due to factors such as decreased glomerular filtration rate and kidney failure, toxins, primarily urea, cannot be excreted and accumulate in the body. When the urea concentration is too high, reaching 20-30 mmol / L, it indicates the onset of end-stage renal disease (ESKD). As a small molecule with high hydrophilicity, urea is difficult to remove using adsorbents; therefore, urease is often used to remove urea in WAK (waxygen ketone) treatments.

[0005] However, a drawback of urease in clearing urea is that the NH3 produced by urease decomposing urea is... 4+ Excessive use also has toxic side effects on the human body. Currently, zirconium phosphate and zirconium oxide ion exchangers are mostly used in WAK to exchange NH4+.4+ While this method can remove certain substances, it consumes a large amount of adsorbent, further increasing the weight of WAK, and the exchange process leads to a significant amount of Na+ in the REDY system. + H + Exudation, etc. Summary of the Invention

[0006] The present invention aims to at least solve one of the technical problems existing in related technologies. To this end, the present invention provides an NH4... + The preparation method of the biotransformation scavenging material includes the following steps:

[0007] S1: Zn(NO3)2 and 3-methyl-1,2,4-triazole are placed in distilled water and stirred to obtain the first mixed solution;

[0008] S2: Add glutamate dehydrogenase to the first mixed solution and stir to obtain a second mixed solution;

[0009] S3: Add ammonia water to the second mixed solution and stir to obtain a third mixed solution;

[0010] S4: Add the third mixed solution dropwise to the Zn(NO3)2 solution and stir to obtain the fourth mixed solution;

[0011] S5: The fourth mixed solution is centrifuged for the first time to obtain a first precipitate. The first precipitate is resuspended in distilled water, and then subjected to ultrasonication and a second centrifugation to obtain a second precipitate. The second precipitate is then freeze-dried to obtain NH4. + Biotransformation removal materials.

[0012] An NH4 according to the present invention + The method for preparing biotransformation scavenging materials, wherein the rotation speed of the first centrifugation and the second centrifugation are both 9000~11000 rpm; and the time of the first centrifugation and the second centrifugation is both 5~10 min.

[0013] An NH4 according to the present invention + A method for preparing biotransformation scavenging materials, wherein the ultrasonic treatment time is 5-10 min.

[0014] An NH4 according to the present invention + A method for preparing biotransformation scavenging materials, wherein the freeze-drying conditions are: maintaining a temperature of -60~40℃ under vacuum for 12~24h.

[0015] An NH4 according to the present invention +A method for preparing biotransformation scavenging materials, wherein the concentration of glutamate dehydrogenase is 0.17~0.67 g / L.

[0016] An NH4 according to the present invention + A method for preparing biotransformation scavenging materials, wherein the concentration of glutamate dehydrogenase is 0.3~0.5 g / L.

[0017] An NH4 as described above + NH4 prepared by a method for biotransformation scavenging materials + Biotransformation scavenging materials, including metal-organic framework materials MAF-7 or ZIF metal-organic framework materials;

[0018] The nodes of the ZIF metal-organic framework material are zinc ions or zinc ion clusters.

[0019] The above-described one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects:

[0020] 1. The present invention provides an NH4 + Biotransformation scavenging materials and their preparation methods, in which urease decomposes urea into NH4 in WAK. + Based on this, glutamate dehydrogenase is used to dehydrogenate the NH4 generated in the reaction. + α-Ketoglutarate and nicotinamide adenine dinucleotide (NADH) are converted into glutamate under the action of enzymes, thereby removing NH4, which is highly toxic to the human body. + Furthermore, the glutamate produced can be efficiently removed using existing adsorbents during subsequent dialysis.

[0021] 2. An NH4 provided by the present invention + A biotransformation scavenging material and its preparation method were described. MAF-7 material was synthesized by reacting zinc nitrate and 3-methyl-1,2,4-triazole (Hmtz) in aqueous solution. Simultaneously, glutamate dehydrogenase was added during the synthesis process, allowing the enzyme to be in situ loaded onto MAF-7, thus achieving enzyme immobilization. This method can not only remove NH4+, a byproduct of peritoneal dialysis fluid regeneration in WAK, but also... + It can effectively remove NH4 and also achieve long-term continuous removal. + .

[0022] 3. An NH4 provided by the present invention + The biotransformation removal material and its preparation method reduce the amount of adsorbent used and the size and weight of the device, which not only improves the treatment efficiency of urea but also solves the problem of Na+ in the REDY system. + H + Risk of leakage.

[0023] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 These are the three types of NH4 prepared in Examples 1-3 of this invention. + Biotransformation removal material for NH4 in buffer solution + Comparison chart showing the effectiveness of the cleaning process.

[0026] Figure 2 The G@MAF-7-2 provided by this invention affects the NH4 in the peritoneal dialysis fluid of patients at different reaction times. + The removal effect was measured.

[0027] Figure 3 This is a schematic diagram of the biocompatibility evaluation of G@MAF-7 provided by the present invention.

[0028] Figure 4 The G@MAF-7-2 material provided by this invention is effective against NH4. + The graph shows the effect of the removal within 24 hours.

[0029] Figure 5 The G@ZIF-90 provided by this invention is for NH4 + The removal effect was measured.

[0030] Figure 6 This is a graph showing the effect of AC and D201 type basic anion exchange resins provided by this invention on the removal of glutamate in the peritoneal dialysis fluid of patients. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention. The following embodiments are used to illustrate this invention but should not be used to limit the scope of this invention.

[0032] Furthermore, the terms “first,” “second,” and “third” are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0033] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0034] The following is combined Figures 1 to 6 Description of an NH4 provided by the present invention + Biotransformation scavenging materials and their preparation methods:

[0035] This invention provides an NH4 + The preparation method of the biotransformation scavenging material includes the following steps:

[0036] S1: Zn(NO3)2 and 3-methyl-1,2,4-triazole are placed in distilled water and stirred to obtain the first mixed solution;

[0037] S2: Add glutamate dehydrogenase to the first mixed solution and stir to obtain a second mixed solution;

[0038] S3: Add ammonia water to the second mixed solution and stir to obtain a third mixed solution;

[0039] S4: Add the third mixed solution dropwise to the Zn(NO3)2 solution and stir to obtain the fourth mixed solution;

[0040] S5: The fourth mixed solution is centrifuged for the first time to obtain a first precipitate. The first precipitate is resuspended in distilled water, and then subjected to ultrasonication and a second centrifugation to obtain a second precipitate. The second precipitate is then freeze-dried to obtain NH4. + Biotransformation removal materials.

[0041] Steps S1, S3, S4, and S5 are steps for preparing the metal-organic framework material MAF-7.

[0042] In one embodiment, the preparation steps of the metal-organic framework material MAF-7 are as follows:

[0043] Weigh 0.357 g of Zn(NO3)2·6H2O and dissolve it in 15 mL of distilled water for later use. Weigh 0.299 g of Hmtz and dissolve it in 10 mL of distilled water. Add 600 μL of 10% ammonia solution, mix well, and bring the volume to 15 mL. Add the above mixture dropwise to the Zn(NO3)2 solution while stirring, and stir at room temperature for 24 h. Then, centrifuge the mixture at 10000 rpm for 5 min, discard the supernatant, resuspend the precipitate in 30 mL of distilled water, sonicate for 5 min, and centrifuge again at 10000 rpm for 5 min. Discard the supernatant and repeat the washing process three times. Freeze-dry the resulting precipitate overnight to obtain the MAF-7 metal-organic framework material.

[0044] Furthermore, adding glutamate dehydrogenase before step S3 allows the NH4 generated from the decomposition of urea by urease in WAK to be converted into NH4. + α-ketoglutarate and nicotinamide adenine dinucleotide (NADH) are converted into glutamate by glutamate dehydrogenase, and glutamate dehydrogenase can also be loaded in situ into MAF-7 to achieve enzyme immobilization.

[0045] Furthermore, metal-organic frameworks (MOFs) refer to porous crystalline materials with periodic network structures formed by the self-assembly of transition metal ions and organic ligands. Compared to traditional immobilized enzyme carriers, MOFs possess higher specific surface area and pore volume, designable and tunable structures and channels, greater diversity, chemical and thermal stability, and milder synthesis conditions, making them widely used in biocatalysis, sensors, and other fields. Loading enzymes onto MOF materials can effectively improve enzyme stability, retain enzyme activity, and enable the repeated use of enzymes. In addition, MAF-7 is a hydrophilic MOF material with a dodecahedral structure and a diameter of approximately 2 μm.

[0046] This invention uses MAF-7 as a carrier, where the metal ions can synergistically enhance enzyme activity and prevent some foreign substances from contacting the enzyme, thus improving enzyme specificity to a certain extent. This allows for the regeneration of NH4, a byproduct of peritoneal dialysis fluid, in WAK. + This invention achieves highly efficient and sustained removal of ammonium ions for over 24 hours, reducing the amount of adsorbent used and the size and weight of the device. Compared to the WAK device developed by Gura et al. and already in clinical trials, which weighs approximately 5 kg and contains 600 g of zirconium phosphate for adsorbing ammonium ions, requiring about 1 kg of zirconium phosphate adsorbent per day, this invention only requires about 100 g of NH4+. +This biotransformation removal material can maintain continuous removal for a long time without replacement, further improving the treatment efficiency of urea and solving the Na+ problem in the REDY system. + H + Risk of leakage.

[0047] An NH4 according to the present invention + The method for preparing biotransformation scavenging materials, wherein the rotation speed of the first centrifugation and the second centrifugation are both 9000~11000 rpm; and the time of the first centrifugation and the second centrifugation is both 5~10 min.

[0048] An NH4 according to the present invention + A method for preparing biotransformation scavenging materials, wherein the ultrasonic treatment time is 5-10 min.

[0049] An NH4 according to the present invention + A method for preparing biotransformation scavenging materials, wherein the freeze-drying conditions are: maintaining a temperature of -60~40℃ under vacuum for 12~24h.

[0050] An NH4 according to the present invention + A method for preparing biotransformation scavenging materials, wherein the concentration of glutamate dehydrogenase is 0.17~0.67 g / L.

[0051] An NH4 according to the present invention + A method for preparing biotransformation scavenging materials, wherein the concentration of glutamate dehydrogenase is 0.3~0.5 g / L.

[0052] An NH4 as described above + NH4 prepared by a method for biotransformation scavenging materials + Biotransformation scavenging materials, including metal-organic framework materials MAF-7 or ZIF metal-organic framework materials;

[0053] The nodes of the ZIF metal-organic framework material are zinc ions or zinc ion clusters.

[0054] The following examples 1-9 illustrate an NH4 provided by the present invention. + The biotransformation scavenging materials and their preparation methods are described.

[0055] Example 1

[0056] Weigh 0.357 g of Zn(NO3)2·6H2O and dissolve it in 15 mL of distilled water for later use. Weigh 0.299 g of Hmtz and dissolve it in 10 mL of distilled water. Add 5 mg of glutamate dehydrogenase and 600 μL of 10% ammonia solution, mix well, and bring the volume to 15 mL. Add the above mixture dropwise to the Zn(NO3)2 solution while stirring at room temperature for 24 h. Then, centrifuge the mixture at 9000 rpm for 10 min, discard the supernatant, resuspend the precipitate in 30 mL of distilled water, sonicate for 10 min, and centrifuge again at 9000 rpm for 10 min. Discard the supernatant and repeat the washing process three times. Freeze-dry the resulting precipitate overnight to obtain NH4. + The biotransformation scavenging material is labeled G@MAF-7-1.

[0057] Example 2

[0058] Weigh 0.357 g of Zn(NO3)2·6H2O and dissolve it in 15 mL of distilled water for later use. Weigh 0.299 g of Hmtz and dissolve it in 10 mL of distilled water. Add 10 mg of glutamate dehydrogenase and 600 μL of 10% ammonia solution, mix well, and bring the volume to 15 mL. Add the above mixture dropwise to the Zn(NO3)2 solution while stirring at room temperature for 24 h. Then, centrifuge the mixture at 10000 rpm for 6 min, discard the supernatant, resuspend the precipitate in 30 mL of distilled water, sonicate for 6 min, and centrifuge again at 10000 rpm for 6 min. Discard the supernatant and repeat the washing process three times. Freeze-dry the resulting precipitate overnight to obtain NH4. + The biotransformation scavenging material is labeled G@MAF-7-2.

[0059] Example 3

[0060] Weigh 0.357 g of Zn(NO3)2·6H2O and dissolve it in 15 mL of distilled water for later use. Weigh 0.299 g of Hmtz and dissolve it in 10 mL of distilled water. Add 20 mg of glutamate dehydrogenase and 600 μL of 10% ammonia solution, mix well, and bring the volume to 15 mL. Add the above mixture dropwise to the Zn(NO3)2 solution while stirring at room temperature for 24 h. Then, centrifuge the mixture at 11000 rpm for 5 min, discard the supernatant, resuspend the precipitate in 30 mL of distilled water, sonicate for 5 min, and centrifuge again at 11000 rpm for 5 min. Discard the supernatant and repeat the washing process three times. Freeze-dry the resulting precipitate overnight to obtain NH4. +The biotransformation scavenging material is labeled G@MAF-7-3.

[0061] Example 4

[0062] Weigh 0.4 g each of materials G@MAF-7-1, G@MAF-7-2, and G@MAF-7-3 from the above examples and place them in three centrifuge tubes respectively. Add 10 mL of NH4 to each tube. + Buffer (NH4) + The concentration was 50 mmol / L. Then, 0.3315 g of NADH and 0.073 g of α-ketoglutarate were added, the pH was adjusted to 7-8, the mixture was mixed thoroughly, the container was sealed with sealing film, and placed in an air shaker. The mixture was shaken at 37 °C for 5, 10, 20, 30, 60, and 120 min, respectively. Afterward, the mixture was removed and centrifuged at 10,000 rpm for 5 min. The supernatant was collected to analyze the NH4+ at different reaction time points. + Clearance amount.

[0063] like Figure 1 As shown, it can be seen that the three materials G@MAF-7-1, G@MAF-7-2, and G@MAF-7-3 all exhibit resistance to NH4+. + All of them have good cleaning effects, with G@MAF-7-2 showing the best cleaning effect.

[0064] Example 5

[0065] Based on the experimental conclusions in Example 4, G@MAF-7-2 was used to treat the NH4 in the patient's peritoneal dialysis fluid. + The removal effect was measured.

[0066] Weigh 0.4 g of G@MAF-7-2 material into a centrifuge tube, add 10 mL of peritoneal dialysis fluid treated with urease (the original urea concentration in the sample was approximately 20 mmol / L), then add 0.3315 g of NADH and 0.073 g of α-ketoglutarate. Mix well, seal tightly with sealing film, and place in an air shaker. React at 37 ℃ for 5, 10, 20, 30, 60, and 120 min, respectively. After each reaction, centrifuge at 10,000 rpm for 5 min, and collect the supernatant to detect NH4+ at different reaction time points. + Clearance amount.

[0067] like Figure 2 As shown, it can be seen that with the extension of reaction time, the G@MAF-7-2 material has a greater effect on NH4+. + The removal effect gradually increased, reaching 80% after 120 minutes of reaction.

[0068] Example 6

[0069] The biocompatibility of G@MAF-7-2 prepared in Example 2 was evaluated, and the specific procedures are as follows:

[0070] (1) Cell culture: Human kidney epithelial cells 293T were cultured in DMEM complete medium (containing DMEM basal medium, 10% fetal bovine serum FBS and 1% penicillin antibiotics) at 37 ℃ in a 5% CO2 cell culture incubator for 4-5 passages. After the cells were viable and stable, they were seeded into plates. 293T cells were seeded into 96-well plates at a density of 1000 cells per well. 100 μL of DMEM complete medium was added to each well and the cells were cultured for another 24 h until the cells were stable.

[0071] (2) Replace the DMEM complete medium with a different conditioned medium:

[0072] A: Positive control: Add 100 μL of DMEM complete culture medium;

[0073] B: Negative control: Add 100 μL of DMEM complete medium containing 5% dimethyl sulfoxide (DMSO);

[0074] C: Experimental group 1: Add 100 μL of DMEM complete culture medium containing 1 mg of MAF-7 material;

[0075] D: Experimental group 2: Add 100 μL of DMEM complete culture medium containing 1 mg G@MAF-7-2 material.

[0076] (3) The cells after the culture medium was changed were cultured in a cell culture incubator for 72 h.

[0077] (4) The cytotoxicity of the materials was detected using a cell proliferation-toxicity assay kit (Cell Counting Kit-8, CCK-8) or the MTT assay:

[0078] After removing the 96-well plate, aspirate the culture medium, add 100 μL of DMEM basal medium containing 10% CCK-8 solution to each well, incubate in a cell culture incubator for 3 h, and then use a microplate reader to detect the absorbance at 450 nm.

[0079] (5) The relative proliferation rate (RGR) of 293T cells was calculated using the following formula:

[0080] RGR = X / X0 × 100%

[0081] Where X is the absorbance value of experimental groups 1 and 2 and the positive control group, and X0 is the absorbance value of the negative control group.

[0082] The evaluation criteria for cytotoxicity are as follows: the cytotoxicity level corresponding to the positive control group must be at least grade 3 to ensure the accuracy of the experimental procedure. If the cytotoxicity level corresponding to the positive control group is less than grade 3, the test needs to be repeated to ensure the accuracy of the experiment. The cytotoxicity grading table is shown in Table 1.

[0083] Table 1 Cytotoxicity Grading Table

[0084]

[0085] Experimental results are as follows Figure 3 As shown, the relative cell proliferation rate of the positive control group was 25.06%, with a toxicity grade of 4, meeting the criteria for a toxicity grade exceeding 3 for the positive control group. In contrast, the cell viability of both the MAF-7 and G@MAF-7-2 groups was above 90%, and there was no significant difference compared to the negative control group. Therefore, from... Figure 3 As can be seen, the toxicity level of all three materials is less than or equal to level 1, which is consistent with the cytotoxicity of biomedical materials.

[0086] Example 7

[0087] This example demonstrates the effect of G@MAF-7-2 on NH4+ in patient peritoneal dialysis fluid. + Experiment to determine the long-term continuous removal effect.

[0088] Nine groups of G@MAF-7-2 materials (0.04 g each) were weighed into centrifuge tubes. 10 mL of peritoneal dialysis fluid treated with urease (the original urea concentration in the sample was approximately 20 mmol / L) was added to each tube. Then, 0.3315 g of NADH and 0.073 g of α-ketoglutarate were added. The tubes were mixed, sealed tightly with sealing film, and placed in an air shaker. The reaction was carried out at 37 °C for 1, 2, 4, 6, 8, 12, 14, 20, and 24 h. After each reaction, the tubes were centrifuged at 10,000 rpm for 5 min, and the supernatant was collected to detect the amount of urea cleared at different reaction time points.

[0089] like Figure 4 As shown, it can be seen that with the extension of reaction time, the G@MAF-7-2 material has a greater effect on NH4+. + The removal effect gradually increases, and it can continuously remove NH4 for up to 24 hours. + This illustrates the NH4 provided by the present invention. + Biotransformation removal materials can maintain continuous NH4 removal for a long time. + .

[0090] Example 8

[0091] Weigh 0.357 g of Zn(NO3)2·6H2O and dissolve it in 15 mL of distilled water for later use. Weigh 0.461 g of imidazole-2-carboxaldehyde (HICA) and dissolve it in 10 mL of distilled water. Add 10 mg of glutamate dehydrogenase and 600 μL of 10% ammonia solution, mix well, and bring the volume to 15 mL. Add the above mixture dropwise to the Zn(NO3)2 solution while stirring at room temperature for 24 h. Then, centrifuge the mixture at 10000 rpm for 6 min, discard the supernatant, resuspend the precipitate in 30 mL of distilled water, sonicate for 6 min, and centrifuge again at 10000 rpm for 6 min. Discard the supernatant and repeat the washing process three times. Freeze-dry the resulting precipitate overnight to obtain NH4. + The biotransformation scavenging material is labeled G@ZIF-90.

[0092] G@ZIF-90 was then used to treat the NH4 in the patient's peritoneal dialysis fluid. + Long-term removal effect determination.

[0093] Weigh 0.4 g of G@ZIF-90 material into a centrifuge tube, add 10 mL of peritoneal dialysis fluid treated with urease (the original urea concentration in the sample was approximately 20 mmol / L), then add 0.3315 g of NADH and 0.073 g of α-ketoglutarate. Mix well, seal tightly with sealing film, and place in an air shaker. React at 37 ℃ for 5, 10, 20, 30, 60, and 120 min, respectively. After each reaction, centrifuge at 10,000 rpm for 5 min, and collect the supernatant to detect NH4+ at different reaction time points. + Clearance amount.

[0094] like Figure 5 As shown, it can be seen that with the extension of reaction time, the G@ZIF-90 material's effect on NH4+ decreases. + The removal effect gradually increased, reaching 70% after 120 minutes of reaction. The G@ZIF-90 material, using other MOF materials in the ZIF series besides MAF-7, still effectively removed NH4. + It has a high removal efficiency.

[0095] Example 9

[0096] This embodiment is a subsequent glutamate clearance experiment performed on peritoneal dialysis fluid containing glutamate, which was treated in Example 5.

[0097] This embodiment uses activated carbon (AC) and D201 type basic anion exchange resin to determine the removal effect of glutamate (Glu) in the peritoneal dialysis fluid of patients. The specific operation is as follows:

[0098] Weigh 0.8 g each of AC and D201 resin materials into centrifuge tubes, add 10 mL of peritoneal dialysis fluid from a peritoneal dialysis patient treated in Example 5, mix well, seal tightly with sealing film, place in an air shaker, and shake at 37 °C for 1 h. After separation, take the supernatant to detect the amount of glutamate clearance.

[0099] like Figure 6 As shown, the D201 type resin can achieve an adsorption capacity of 125 mg / g, exhibiting good glutamic acid scavenging effect.

[0100] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A NH4 + The method for producing a bioconversion scavenging material is characterized by, The method comprises the following steps: S1: Zn(NO3)2 and 3-methyl-1,2,4-triazole are placed in distilled water and stirred to obtain a first mixed solution; S2: glutamate dehydrogenase is added to the first mixed solution and stirred to obtain a second mixed solution; S3: ammonia water is added to the second mixed solution and stirred to obtain a third mixed solution; S4: the third mixed solution is added dropwise to a Zn(NO3)2 solution and stirred to obtain a fourth mixed solution; S5: centrifuging the fourth mixed solution for the first time to obtain a first precipitate, resuspending the first precipitate with distilled water, performing ultrasonic treatment and second centrifugation to obtain a second precipitate, and performing freeze-drying on the second precipitate to obtain NH4 + biotransformation scavenging material.

2. A NH4 + The method for producing a bioconversion scavenging material is characterized by, The rotation speed of the first centrifugation and the second centrifugation is 9000-11000 rpm; the time of the first centrifugation and the second centrifugation is 5-10 min.

3. A NH4 according to claim 1 + The method for preparing a bioconversion scavenging material, characterized by, The ultrasonic treatment time is 5-10 min.

4. A NH4 according to claim 1 + The method for preparing a bioconversion scavenging material is characterized by, The freeze-drying condition is that the temperature is kept at-60-40℃ under vacuum for 12-24 h.

5. A NH4 + The method for producing a bioconversion scavenging material is characterized by, The concentration of the glutamate dehydrogenase is 0.17-0.67 g / L.

6. A NH4 + The method for preparing a bioconversion scavenging material is characterized by, The concentration of the glutamate dehydrogenase is 0.3-0.5 g / L.

7. A NH4 + NH4 + The biotransformation scavenger material is characterized in that, The metal organic framework material MAF-7 is included.

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