NH4 < + > biotransformation removing material and preparation method thereof

Abstract

The invention relates to the technical field of biological medicine, and provides an NH4 < + > biotransformation removal material and a preparation method thereof, glutamate dehydrogenase is adopted, NH4 < + > generated by decomposing urea by urease, alpha-ketoglutaric acid and nicotinamide adenine dinucleotide are converted into glutamic acid under the action of enzyme, so that NH4 < + > with high toxicity to human bodies is removed. Besides, zinc nitrate and 3-methyl-1, 2, 4-triazole react in an aqueous solution to synthesize an MAF-7 material, and glutamate dehydrogenase is added in the synthesis process, so that enzyme is loaded into MAF-7 in situ, and enzyme immobilization is realized. According to the material, efficient removal of a peritoneal dialysis liquid regeneration byproduct NH4 < + > in WAK can be achieved, long-time continuous removal of NH4 < + > can be achieved, the dosage of an adsorbent and the volume and weight of a device are reduced, the treatment efficiency of urea is further improved, and the risk that Na < + > and H < + > seep out of an REDY system is solved.

Description

Technical Field

[0001] The present invention relates to the field of biomedical technology, and in particular to a NH 4+ Biotransformation scavenging materials and methods for preparing the same. Background Art

[0002] The reduction and damage of kidney function will lead to a large number of toxins in the body that cannot be excreted, such as urea, creatinine, uric acid, etc. The accumulation of these toxins will further lead to a series of kidney diseases, such as renal failure, uremia, etc. The wearable artificial kidney (WAK) can achieve efficient and continuous removal of uremic toxins because of its complete dialysis device and process.

[0003] Currently, most systems that meet WAK requirements are REcirculating DialYsissorbent system (REDY) filters. The toxin removal part of the REDY filter is mainly composed of activated carbon, urease, and zirconium oxide zirconium phosphate ion exchanger. First, the peritoneal dialysis fluid passes through the activated carbon part to remove most of the non-urea organic compounds; then urease decomposes urea into carbonate and NH 4 + NH 4 + Exchange for Na + and H + , in order to achieve the purpose of removing urea.

[0004] Urea is a toxin that is difficult to remove. It is also called urea or carbonamide. It is a white or colorless needle-shaped or rod-shaped crystal with a chemical formula of CO(NH 2 ) 2 , which is the main nitrogenous waste produced by the circulation metabolism in mammals, is usually excreted from the body through urine or sweat. Urea, as a form of detoxification of ammonia by the human body, has good water solubility and can generally be transported to the kidneys through the blood and excreted from the body with urine, accounting for about 90% of renal excretion. Its maximum daily production is about 240~470 mmol. However, due to factors such as decreased glomerular filtration rate and renal failure, toxins mainly composed of urea cannot be excreted from the body and accumulate in the body. When the concentration of urea is too high, reaching 20~30 mmol / L, it indicates the occurrence of end-stage kidney disease (ESKD). Urea, as a small molecule with high hydrophilicity, is difficult to remove by adsorbents and other methods. Therefore, urease is mostly used to remove urea in WAK.

[0005] However, the disadvantage of urease in removing urea is that urease decomposes urea to produce NH4+ Excessive use also has toxic side effects on the human body. Currently, WAK mostly uses zirconium phosphate zirconium oxide ion exchangers for NH 4+ However, this method consumes a large amount of adsorbent, further increasing the weight of WAK, and the exchange process will cause a large amount of Na in the REDY system. + , H + Exudation, etc. Summary of the invention

[0006] The present invention aims to solve at least one of the technical problems existing in the related art. To this end, the present invention provides a NH 4 + The preparation method of the biotransformation removal material comprises the following steps: S1: Zn(NO 3 ) 2 and 3-methyl-1,2,4-triazole are placed in distilled water and stirred to obtain a first mixed solution; S2: adding glutamate dehydrogenase to the first mixed solution and stirring to obtain a second mixed solution; S3: adding aqueous ammonia to the second mixed solution and stirring to obtain a third mixed solution; S4: Add the third mixed solution dropwise to the Zn(NO 3 ) 2 The solution is stirred to obtain a fourth mixed solution; 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 ultrasonic treatment and a second centrifugation treatment to obtain a second precipitate, and the second precipitate is freeze-dried to obtain NH 4 + Biotransformation removes materials.

[0007] According to the present invention, a NH 4 + The preparation method of the biotransformation removal material, the rotation speed of the first centrifugation and the second centrifugation are both 9000-11000 rpm; the time of the first centrifugation and the second centrifugation are both 5-10 minutes.

[0008] According to the present invention, a NH 4 + The preparation method of the biotransformation removal material, wherein the ultrasonic treatment time is 5 to 10 minutes.

[0009] According to the present invention, a NH 4 +The preparation method of the biotransformation removal material comprises the following freeze-drying conditions: maintaining the temperature at -60 to 40°C under vacuum conditions for 12 to 24 hours.

[0010] According to the present invention, a NH 4 + A method for preparing a bioconversion removal material, wherein the concentration of the glutamate dehydrogenase is 0.17-0.67 g / L.

[0011] According to the present invention, a NH 4 + The preparation method of the bioconversion removal material, wherein the concentration of the glutamate dehydrogenase is 0.3-0.5 g / L.

[0012] A NH as described above 4 + Preparation method of biotransformation scavenging material for preparing NH 4 + Biotransformation removal materials, including metal organic framework materials MAF-7 or ZIF metal organic framework materials; Wherein, the nodes of the ZIF metal organic framework material are metal zinc ions or metal zinc ion clusters.

[0013] The above one or more technical solutions in the embodiments of the present invention have at least one of the following technical effects: 1. A NH provided by the present invention 4 + Bioconversion scavenging material and preparation method thereof, wherein urease decomposes urea into NH 4 + Based on the glutamate dehydrogenase, the NH 4 + α-ketoglutarate and nicotinamide adenine dinucleotide (NADH) are converted into glutamate under the action of enzymes to remove NH 4 + , and the produced glutamate can be efficiently removed by existing adsorbents during the subsequent dialysis process.

[0014] 2. A NH provided by the present invention 4 + Biotransformation removal material and preparation method thereof, zinc nitrate and 3-methyl-1,2,4-triazole (Hmtz) are reacted in aqueous solution to synthesize MAF-7 material, and glutamate dehydrogenase is added during the synthesis process to load the enzyme in situ into MAF-7 to achieve enzyme immobilization. It can not only achieve the regeneration of peritoneal dialysis fluid byproduct NH 4 + It can also achieve long-term continuous removal of NH4 + .

[0015] 3. A NH provided by the present invention 4 + The bioconversion removal material and its preparation method reduce the amount of adsorbent and the volume and weight of the device, which can not only improve the treatment efficiency of urea, but also solve the problem of Na + , H + Risk of leakage.

[0016] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 The three NH prepared in Examples 1-3 provided by the present invention are 4 + Biotransformation removal material to NH in buffer 4 + Comparison chart of the removal effect determination.

[0019] Figure 2 The G@MAF-7-2 provided by the present invention reacts with the patient's peritoneal dialysis fluid NH at different reaction times. 4 + The cleaning effect determination diagram.

[0020] Figure 3 It is a schematic diagram of the biocompatibility evaluation of G@MAF-7 provided by the present invention.

[0021] Figure 4 The G@MAF-7-2 material provided by the present invention is 4 + Figure 2 shows the clearance effect within 24 hours.

[0022] Figure 5 The G@ZIF-90 provided by the present invention is 4 + The cleaning effect determination diagram.

[0023] Figure 6The figure is a measurement chart of the clearance effect of AC and D201 basic anion exchange resins provided by the present invention on glutamate in the peritoneal dialysis fluid of patients. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical scheme and advantages of the present invention clearer, the technical scheme of the present invention will be clearly and completely described below in conjunction with the drawings in the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention. The following embodiments are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0025] Furthermore, the terms “first”, “second”, and “third” are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0026] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0027] Combine the following Figures 1 to 6 The present invention provides a NH 4 + Biotransformation removal materials and preparation methods thereof: The present invention provides a NH 4 + The preparation method of the biotransformation removal material comprises the following steps: S1: Zn(NO 3 ) 2 and 3-methyl-1,2,4-triazole are placed in distilled water and stirred to obtain a first mixed solution; S2: adding glutamate dehydrogenase to the first mixed solution and stirring to obtain a second mixed solution; S3: adding aqueous ammonia to the second mixed solution and stirring to obtain a third mixed solution; S4: Add the third mixed solution dropwise to the Zn(NO 3 )2 The solution is stirred to obtain a fourth mixed solution; 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 ultrasonic treatment and a second centrifugation treatment to obtain a second precipitate, and the second precipitate is freeze-dried to obtain NH 4 + Biotransformation removes materials.

[0028] Among them, steps S1, S3, S4 and S5 are steps for preparing the metal organic framework material MAF-7.

[0029] In one embodiment, the preparation steps of the metal organic framework material MAF-7 are as follows: Weigh 0.357 g of Zn(NO 3 ) 2 6H 2 O was dissolved in 15 mL of distilled water for later use; 0.299 g of Hmtz was weighed and dissolved in 10 mL of distilled water, 600 μL of 10% ammonia water was added, mixed, and the volume was adjusted to 15 mL; the above mixed solution was added dropwise to Zn(NO 3 ) 2 The mixture was centrifuged at 10,000 rpm for 5 min, the supernatant was discarded, the precipitate was resuspended in 30 mL of distilled water, ultrasonically treated for 5 min, centrifuged again at 10,000 rpm for 5 min, the supernatant was discarded, and the washing was repeated 3 times. The obtained precipitate was freeze-dried overnight to obtain the MAF-7 metal organic framework material.

[0030] Furthermore, glutamate dehydrogenase is added before step S3 to decompose urea into NH 4 + α-ketoglutarate and nicotinamide adenine dinucleotide (NADH) are converted into glutamate under the action of glutamate dehydrogenase, and glutamate dehydrogenase can also be loaded into MAF-7 in situ to achieve enzyme immobilization.

[0031] Furthermore, Metal-Organic Frameworks (MOF) refers to a crystalline porous material with a periodic network structure formed by self-assembly of transition metal ions and organic ligands. Compared with traditional immobilized enzyme carriers, it has a higher specific surface area and pore volume, a designable and regulated structure and pores, a variety of species, chemical and thermal stability, and mild synthesis conditions. It is widely used in biocatalysis, sensors and other fields. Using MOF materials to load enzymes can effectively improve the stability of enzymes, retain enzyme activity, and achieve multiple uses of enzymes. In addition, MAF-7 is a hydrophilic MOF material with a dodecahedral structure and a diameter of about 2 μm.

[0032] The present invention uses MAF-7 as a carrier, in which the metal ions can produce a synergistic effect with the enzyme, improve the enzyme activity, and prevent some foreign matter from contacting the enzyme, thereby improving the specificity of the enzyme to a certain extent, and achieving the regeneration of the peritoneal dialysis byproduct NH in WAK. 4 + The device can remove ammonium ions efficiently and continuously for more than 24 hours, reducing the amount of adsorbent and the volume and weight of the device. Compared with the WAK device developed by Gura et al. and used in clinical trials, it weighs about 5 kg, of which 600 g of zirconium phosphate is used to adsorb ammonium ions. About 1 kg of zirconium phosphate adsorbent is consumed in one day, while the present invention only consumes about 100 g of NH 4 + The biological conversion removes the material and can maintain continuous removal for a long time without replacement, further improving the treatment efficiency of urea and solving the problem of Na + , H + Risk of leakage.

[0033] According to the present invention, a NH 4 + The preparation method of the biotransformation removal material, the rotation speed of the first centrifugation and the second centrifugation are both 9000-11000 rpm; the time of the first centrifugation and the second centrifugation are both 5-10 minutes.

[0034] According to the present invention, a NH 4 + The preparation method of the biotransformation removal material, wherein the ultrasonic treatment time is 5 to 10 minutes.

[0035] According to the present invention, a NH 4 + The preparation method of the biotransformation removal material comprises the following freeze-drying conditions: maintaining the temperature at -60 to 40°C under vacuum conditions for 12 to 24 hours.

[0036] According to the present invention, a NH 4 + A method for preparing a bioconversion removal material, wherein the concentration of the glutamate dehydrogenase is 0.17-0.67 g / L.

[0037] According to the present invention, a NH 4 + The preparation method of the bioconversion removal material, wherein the concentration of the glutamate dehydrogenase is 0.3-0.5 g / L.

[0038] A NH as described above 4 + Preparation method of biotransformation scavenging material for preparing NH 4 + Biotransformation removal materials, including metal organic framework materials MAF-7 or ZIF metal organic framework materials; Wherein, the nodes of the ZIF metal organic framework material are metal zinc ions or metal zinc ion clusters.

[0039] The following is a NH 4 + Biotransformation scavenging materials and methods for their preparation are described.

[0040] Example 1 Weigh 0.357 g of Zn(NO 3 ) 2 6H 2 O was dissolved in 15 mL of distilled water for later use; 0.299 g of Hmtz was weighed and dissolved in 10 mL of distilled water, 5 mg of glutamate dehydrogenase was added, and 600 μL of 10% ammonia water was added, mixed, and the volume was adjusted to 15 mL; the above mixed solution was added dropwise to Zn(NO 3 ) 2 The mixture was then centrifuged at 9000 rpm for 10 min, the supernatant was discarded, the precipitate was resuspended in 30 mL of distilled water, ultrasonically treated for 10 min, centrifuged again at 9000 rpm for 10 min, the supernatant was discarded, and the washing was repeated 3 times. The obtained precipitate was freeze-dried overnight to obtain NH 4 + Biotransformation cleared the material and labeled it as G@MAF-7-1.

[0041] Example 2 Weigh 0.357 g of Zn(NO 3 ) 2 6H 2O was dissolved in 15 mL of distilled water for later use; 0.299 g of Hmtz was weighed and dissolved in 10 mL of distilled water, 10 mg of glutamate dehydrogenase was added, and 600 μL of 10% ammonia water was added, mixed, and the volume was adjusted to 15 mL; the above mixed solution was added dropwise to Zn(NO 3 ) 2 The mixture was then centrifuged at 10,000 rpm for 6 min, the supernatant was discarded, the precipitate was resuspended in 30 mL of distilled water, ultrasonically treated for 6 min, centrifuged again at 10,000 rpm for 6 min, the supernatant was discarded, and the washing was repeated 3 times. The obtained precipitate was freeze-dried overnight to obtain NH 4 + Biotransformation cleared the material and labeled it as G@MAF-7-2.

[0042] Example 3 Weigh 0.357 g of Zn(NO 3 ) 2 6H 2 O was dissolved in 15 mL of distilled water for later use; 0.299 g of Hmtz was weighed and dissolved in 10 mL of distilled water, 20 mg of glutamate dehydrogenase was added, and 600 μL of 10% ammonia water was added, mixed, and the volume was adjusted to 15 mL; the above mixed solution was added dropwise to Zn(NO 3 ) 2 The mixture was then centrifuged at 11,000 rpm for 5 min, the supernatant was discarded, the precipitate was resuspended in 30 mL of distilled water, ultrasonically treated for 5 min, centrifuged again at 11,000 rpm for 5 min, the supernatant was discarded, and the washing was repeated 3 times. The obtained precipitate was freeze-dried overnight to obtain NH 4 + Biotransformation cleared the material and labeled it as G@MAF-7-3.

[0043] Example 4 Weigh 0.4 g of each of the G@MAF-7-1, G@MAF-7-2, and G@MAF-7-3 materials in the above examples and place them in three centrifuge tubes, and add 10 mL of NH 4 + Buffer (NH 4 +The concentration was 50 mmoL / L), and then 0.3315 g NADH and 0.073 g α-ketoglutaric acid were added, and the pH value was adjusted to 7-8. After mixing, the lid was tightly sealed with a sealing film, and placed in an air shaker. After oscillation reaction at 37 °C for 5, 10, 20, 30, 60 and 120 min, the tubes were taken out and centrifuged at 10000 rpm for 5 min. The supernatant was taken to detect NH 4 + Clearance amount.

[0044] like Figure 1 As shown in the figure, it can be seen that G@MAF-7-1, G@MAF-7-2 and G@MAF-7-3 are all NH 4 + All of them have good cleaning effects, and G@MAF-7-2 has the best cleaning effect.

[0045] Example 5 According to the experimental conclusion in Example 4, G@MAF-7-2 was used to treat the patient's peritoneal dialysis fluid NH 4 + The cleaning effect was measured.

[0046] Weigh 0.4 g of G@MAF-7-2 material in a centrifuge tube, add 10 mL of urease-treated peritoneal dialysis fluid from peritoneal dialysis patients (the original urea concentration in the sample is about 20 mmoL / L), then add 0.3315 g of NADH and 0.073 g of α-ketoglutaric acid, mix well, cover tightly, seal with sealing film, place in an air shaker, shake at 37 °C for 5, 10, 20, 30, 60 and 120 min, take out and centrifuge at 10000 rpm for 5 min, take the supernatant to detect NH at different reaction time periods 4 + Clearance amount.

[0047] like Figure 2 As shown in the figure, it can be seen that with the extension of reaction time, the G@MAF-7-2 material has a 4 + The removal effect gradually increased, and at 120 minutes of reaction, the removal effect reached 80%.

[0048] Example 6 The biocompatibility of G@MAF-7-2 prepared in Example 2 was evaluated as follows: (1) Cell culture: Human renal epithelial 293T cells were cultured in DMEM complete medium (containing DMEM basal medium, 10% fetal bovine serum (FBS) and 1% double antibody) at 37°C and 5% CO 2The cells were cultured in a cell culture incubator for 4-5 generations and plated after cell viability and status were stable. 293T cells were seeded in a 96-well plate at a density of 1000 cells per well, 100 μL of DMEM complete medium was added to each well and cultured for 24 h until the cell status was stable.

[0049] (2) Replace DMEM complete medium with different conditioned medium: A: Positive control: add 100 μL DMEM complete medium; B: Negative control: add 100 μL of DMEM complete medium containing 5% dimethyl sulfoxide (DMSO); C: Experimental group 1: 100 μL of DMEM complete medium containing 1 mg of MAF-7 material was added; D: Experimental group 2: Add 100 μL of DMEM complete medium containing 1 mg of G@MAF-7-2 material.

[0050] (3) After replacing the culture medium, the cells were cultured in a cell culture incubator for 72 h.

[0051] (4) Detect the cytotoxicity of the material using a cell proliferation-toxicity detection kit (Cell Counting Kit-8, CCK-8) or MTT colorimetric assay: After taking out the 96-well plate, the culture medium was aspirated, and 100 μL of DMEM basal culture medium containing 10% CCK-8 solution was added to each well. After incubation in a cell culture incubator for 3 h, the absorbance at 450 nm was detected using an ELISA reader.

[0052] (5) Calculate the relative proliferation rate RGR of 293T cells according to the following formula: RGR=X / X 0 ×100% Among them, X is the absorbance value of experimental group 1, 2 and positive control group, X 0 is the absorbance value of the negative control group.

[0053] The evaluation criteria for cytotoxicity are: the cytotoxicity level corresponding to the positive control group is at least level 3 to ensure the accuracy of the experimental operation. If the cytotoxicity level corresponding to the positive control group is less than level 3, it needs to be retested to ensure the accuracy of the experiment. The cytotoxicity grading table is shown in Table 1.

[0054] Table 1 Cytotoxicity grading table

[0055] The experimental results are as follows Figure 3As shown in the figure, the relative proliferation rate of cells in the positive control group was 25.06%, and the toxicity level was level 4, which met the standard that the toxicity level of the positive control group exceeded level 3. The cell activities of the MAF-7 and G@MAF-7-2 groups were both above 90%, and there was no significant difference with the negative control group. Figure 3 It can be seen that the toxicity levels of the three materials are all less than or equal to level 1, which is consistent with the cytotoxicity of biomedical materials.

[0056] Example 7 This example shows that G@MAF-7-2 is effective for the treatment of NH 4 + Experiment to determine the long-term sustained clearance effect.

[0057] Weigh 0.04 g of G@MAF-7-2 material (9 groups in total) into centrifuge tubes, add 10 mL of urease-treated peritoneal dialysis fluid from peritoneal dialysis patients (the original urea concentration in the sample was about 20 mmoL / L), add 0.3315 g of NADH and 0.073 g of α-ketoglutaric acid, mix well, cover tightly, and seal with sealing film. Place in an air shaker and shake at 37 °C for 1, 2, 4, 6, 8, 12, 14, 20 and 24 h, respectively, then take out and centrifuge at 10000 rpm for 5 min, and take the supernatant to detect the urea clearance at different reaction time periods.

[0058] like Figure 4 As shown in the figure, it can be seen that with the extension of reaction time, the G@MAF-7-2 material has a 4 + The scavenging effect gradually increased, and NH 4 + , indicating that the NH provided by the present invention 4 + Biotransformation removal materials can maintain long-term continuous removal of NH 4 + .

[0059] Example 8 Weigh 0.357 g of Zn(NO 3 ) 2 6H 2 O was dissolved in 15 mL of distilled water for later use; 0.461 g of imidazole-2-carboxaldehyde (HICA) was weighed and dissolved in 10 mL of distilled water, 10 mg of glutamate dehydrogenase was added, and 600 μL of 10% ammonia water was added, mixed, and the volume was adjusted to 15 mL; the above mixed solution was added dropwise to Zn(NO 3 ) 2The mixture was then centrifuged at 10,000 rpm for 6 min, the supernatant was discarded, the precipitate was resuspended in 30 mL of distilled water, ultrasonically treated for 6 min, centrifuged again at 10,000 rpm for 6 min, the supernatant was discarded, and the washing was repeated 3 times. The obtained precipitate was freeze-dried overnight to obtain NH 4 + Biotransformation scavenged the material and labeled it as G@ZIF-90.

[0060] G@ZIF-90 was then used to treat the patient's peritoneal dialysis fluid NH 4 + Determination of long-term clearance effect.

[0061] Weigh 0.4 g of G@ZIF-90 material in a centrifuge tube, add 10 mL of urease-treated peritoneal dialysis fluid from peritoneal dialysis patients (the original urea concentration in the sample is about 20 mmoL / L), then add 0.3315 g of NADH and 0.073 g of α-ketoglutaric acid, mix well, cover tightly, seal with sealing film, place in an air shaker, shake at 37 °C for 5, 10, 20, 30, 60 and 120 min, then take out and centrifuge at 10000 rpm for 5 min, take the supernatant to detect NH at different reaction time periods 4 + Clearance amount.

[0062] like Figure 5 As shown in the figure, it can be seen that with the extension of reaction time, the G@ZIF-90 material has a 4 + The removal effect of NH4+ was gradually enhanced, and the removal effect reached 70% at 120 min. G@ZIF-90 material uses other MOF materials in the ZIF series other than MAF-7. 4 + Has a higher removal efficiency.

[0063] Example 9 This example is a subsequent glutamate clearance experiment on the peritoneal dialysis fluid containing glutamate treated in Example 5.

[0064] This example uses activated carbon (AC) and D201 basic anion exchange resin to measure the removal effect of glutamate (Glu) in the patient's peritoneal dialysis fluid. The specific operation is as follows: Weigh 0.8 g of AC and D201 resin materials respectively into a centrifuge tube, add 10 mL of peritoneal dialysis fluid from a peritoneal dialysis patient treated in Example 5, mix well, cover tightly, and seal with a sealing film. Place in an air shaker, shake at 37°C for 1 h, take out and separate, and take the supernatant to detect glutamate clearance.

[0065] like Figure 6 As shown, it can be seen that the D201 resin can reach an adsorption capacity of 125 mg / g and has a good glutamate removal effect.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A NH4 + The method for preparing a bioconversion removal material is characterized in that: The steps include: S1: placing Zn(NO3)2 and 3-methyl-1,2,4-triazole in distilled water and stirring to obtain a first mixed solution; S2: adding glutamate dehydrogenase to the first mixed solution and stirring to obtain a second mixed solution; S3: adding aqueous ammonia to the second mixed solution and stirring to obtain a third mixed solution; S4: adding the third mixed solution dropwise to the Zn(NO3)2 solution, stirring, to obtain a fourth mixed solution; 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 after ultrasonic treatment and a second centrifugation treatment, a second precipitate is obtained, and the second precipitate is freeze-dried to obtain NH4 + Biotransformation removes materials.

2. A NH4 according to claim 1 + The method for preparing a bioconversion removal material is characterized in that: The rotation speeds of the first centrifugation and the second centrifugation are both 9000-11000 rpm; the time of the first centrifugation and the second centrifugation is both 5-10 min.

3. A NH4 according to claim 1 + The method for preparing a bioconversion removal material is characterized in that: The ultrasonic treatment time is 5 to 10 minutes.

4. A NH4 according to claim 1 + The method for preparing a bioconversion removal material is characterized in that: The freeze-drying conditions are: maintaining the temperature at -60 to 40° C. under vacuum conditions for 12 to 24 hours.

5. A NH4 according to claim 1 + The method for preparing a bioconversion removal material is characterized in that: The concentration of the glutamate dehydrogenase is 0.17-0.67 g / L.

6. A NH4 according to claim 1 + The method for preparing a bioconversion removal material is characterized in that: The concentration of the glutamate dehydrogenase is 0.3-0.5 g / L.

7. An NH4 as claimed in any one of claims 1 to 6 + Preparation method of biological transformation removal material to prepare NH4 + Biotransformation scavenging material, characterized in that Including metal organic framework material MAF-7; Alternatively, it comprises a ZIF metal-organic framework material, wherein the nodes of the ZIF metal-organic framework material are metal zinc ions or metal zinc ion clusters.

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