CN118384862A - Protein-bound toxin adsorbent and preparation method and application thereof - Google Patents

Abstract

The invention provides a protein-bound toxin adsorbent, a preparation method and application thereof, wherein the protein-bound toxin adsorbent takes ultrahigh crosslinked styrene-divinylbenzene resin as a carrier, polyethyleneimine is fixedly loaded on the carrier, and is connected with an adsorption ligand, and the adsorption ligand comprises at least one of alpha-methyl-4- (2-methylpropyl) phenylacetic acid, oleic acid and linoleic acid. The protein-bound toxin adsorbent disclosed by the invention enables the protein-bound toxin to be in a free state through the action of an adsorption ligand, and simultaneously eliminates the free protein-bound toxin through the adsorption action of the ultra-high crosslinked styrene-divinylbenzene resin and the electrostatic binding action of the polyethylenimine, so that the clearance rate of the protein-bound toxin is improved.

Description

A protein-bound toxin adsorbent and its preparation method and application

Technical Field

The present invention relates to the technical field of blood purification, and in particular to a protein-bound toxin adsorbent and a preparation method and application thereof.

Background technique

Uremia, also known as end-stage renal disease, is a clinical syndrome of the end stage of chronic renal failure. The concentration of more than 200 substances in the body of uremia patients is higher than that of normal people. According to the biochemical properties of these substances, they are mainly divided into three categories: small molecule water-soluble solutes, medium and large molecule toxins, and protein-bound toxins.

The relative molecular mass of protein-bound toxins is usually less than 500. Although the relative molecular mass of protein-bound toxins is small, protein-bound toxins are easily bound to serum proteins to form a larger protein-bound form, which accumulates in the body of uremic patients. The accumulation of protein-bound toxins in uremic patients can damage the functions of various systems and cause complications. A large number of studies have shown that protein-bound toxins (PBUTs) are involved in the progression of chronic renal failure and are closely related to renal interstitial fibrosis and cardiovascular complications of CKD. Therefore, it is necessary to remove protein-bound toxins in uremic patients.

Traditional dialysis, filtration, diafiltration and high-flux dialysis technologies have limited ability to remove protein-bound toxins. The existing blood purification system that combines adsorbents and dialyzers has significantly improved the ability to remove protein-bound toxins compared to traditional blood purification methods such as dialysis, but the removal effect of these blood purification systems on protein-bound toxins is still unsatisfactory. In addition, the adsorbents in the existing blood purification systems lack selectivity for the adsorption of protein-bound toxins.

Summary of the invention

The present invention aims to solve the problem that the prior art has poor effect in clearing protein-bound toxins.

To solve the above problems, the first aspect of the present invention provides a protein-bound toxin adsorbent, which uses ultra-high cross-linked styrene-divinylbenzene resin as a carrier, on which polyethyleneimine is immobilized, and the polyethyleneimine is connected to an adsorption ligand, and the adsorption ligand includes at least one of α-methyl-4-(2-methylpropyl)phenylacetic acid, oleic acid and linoleic acid.

Furthermore, the ultra-high cross-linked styrene-divinylbenzene resin is prepared by cross-linking reaction of low-cross-linked styrene-divinylbenzene copolymer, the polyethyleneimine is introduced during the cross-linking reaction of the low-cross-linked styrene-divinylbenzene copolymer, the adsorption ligand is connected to the polyethyleneimine by electrostatic adsorption, and the solid loading range of the polyethyleneimine is 0.1mmol/g to 1mmol/g.

The second aspect of the present invention provides a method for preparing a protein-bound toxin adsorbent, which is used to prepare the protein-bound toxin adsorbent described in the first aspect, and the preparation method comprises:

Preparation of low cross-linked styrene-divinylbenzene copolymers;

The low-crosslinked styrene-divinylbenzene copolymer undergoes a crosslinking reaction to prepare an ultra-high crosslinked styrene-divinylbenzene resin, wherein polyethyleneimine is immobilized on the ultra-high crosslinked styrene-divinylbenzene resin, and the polyethyleneimine is immobilized on the ultra-high crosslinked styrene-divinylbenzene resin during the crosslinking reaction of the low-crosslinked styrene-divinylbenzene copolymer;

The ultra-high cross-linked styrene-divinylbenzene resin is soaked in an adsorption ligand solution. After the soaking is completed, the adsorption ligand is connected to the polyethyleneimine to obtain a protein-bound toxin adsorbent.

Furthermore, the low cross-linked styrene-divinylbenzene copolymer is subjected to a cross-linking reaction to prepare an ultra-high cross-linked styrene-divinylbenzene resin, comprising:

The low-crosslinked styrene-divinylbenzene copolymer is subjected to a chloromethylation reaction, and polyethyleneimine is added during the chloromethylation reaction to obtain a low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine;

The low cross-linked styrene-divinylbenzene copolymer containing polyethyleneimine is subjected to Friedel-Crafts reaction to obtain an ultra-high cross-linked styrene-divinylbenzene resin.

Further, the low cross-linked styrene-divinylbenzene copolymer is subjected to a chloromethylation reaction, and polyethyleneimine is added during the chloromethylation reaction to obtain a low cross-linked styrene-divinylbenzene copolymer containing polyethyleneimine, comprising:

After a low-crosslinked styrene-divinylbenzene copolymer is added to ethylene dichloride for swelling, the swollen low-crosslinked styrene-divinylbenzene copolymer, chloromethyl ether and anhydrous ferric chloride are refluxed at 50° C. to 60° C. for 2 h to 4 h, and then the temperature is raised to 80° C. to 100° C. for further reflux reaction for 5 h to 24 h. Meanwhile, polyethyleneimine is added during the heating process for reaction, and the polyethyleneimine is introduced into the low-crosslinked styrene-divinylbenzene copolymer to obtain a low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine.

Furthermore, the mass ratio of the low-crosslinked styrene-divinylbenzene copolymer to the chloromethyl ether is 1:4 to 1:6, the mass ratio of the low-crosslinked styrene-divinylbenzene copolymer to the anhydrous ferric chloride is 1:0.5 to 1:1.5; the mass ratio of the low-crosslinked styrene-divinylbenzene copolymer to the polyethyleneimine is 20:5 to 20:20.

Furthermore, the low cross-linked styrene-divinylbenzene copolymer containing polyethyleneimine is subjected to a Friedel-Crafts reaction to obtain an ultra-high cross-linked styrene-divinylbenzene resin, comprising:

The low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine and nitrobenzene are mixed, and then allowed to stand at 35° C. to 45° C. for 4 to 5 hours, and then zinc chloride is added under stirring to carry out Friedel-Crafts reaction to form an ultra-high crosslinked styrene-divinylbenzene resin, wherein the temperature of the Friedel-Crafts reaction is 110° C. to 130° C., and the reaction time is 8 to 16 hours.

Furthermore, the ultra-high cross-linked styrene-divinylbenzene resin is soaked in an adsorption ligand solution, and after the soaking, the adsorption ligand is connected to the polyethyleneimine to obtain a protein-bound toxin adsorbent, comprising:

The ultra-high cross-linked styrene-divinylbenzene resin is immersed in an alkaline solution until the pH value of the alkaline solution remains unchanged to obtain the transformed ultra-high cross-linked styrene-divinylbenzene resin; the transformed ultra-high cross-linked styrene-divinylbenzene resin is washed and dried, and then immersed in an adsorption ligand solution; after the soaking, the resin is washed to obtain a protein-bound toxin adsorbent, wherein the mass percentage of the adsorption ligand in the adsorption ligand solution is 10% to 40%.

Furthermore, the transformed ultra-high cross-linked styrene-divinylbenzene resin is washed with deionized water. After the ultra-high cross-linked styrene-divinylbenzene resin is immersed in the adsorption ligand, it is washed with deionized water.

The third aspect of the present invention provides a blood perfusion device, comprising the protein-bound toxin adsorbent as described in the first aspect, or the protein-bound toxin adsorbent prepared by the preparation method as described in the second aspect.

The protein-bound toxin adsorbent of the present invention uses ultra-high cross-linked styrene-divinylbenzene resin as a carrier, immobilizes polyethyleneimine, polyethyleneimine is connected with an adsorption ligand, the adsorption ligand has a negative charge, and the protein-bound toxin adsorbent is contacted with blood, and the adsorption ligand falls off the protein-bound toxin adsorbent and enters the blood. The adsorption ligand has the same albumin binding site as p-cresol sulfate and indoxyl sulfate, and can compete with protein-bound toxins for adsorption on albumin. The binding force between the adsorption ligand and albumin is stronger than the binding force between the protein-bound toxin and albumin, so that the protein-bound toxin falls off from the albumin, allowing the protein-bound toxin to be adsorbed on the albumin. The protein-bound toxin is in a free state, which is convenient for the ultra-high cross-linked styrene-divinylbenzene resin and the polyethyleneimine immobilized thereon to adsorb the protein-bound toxin, thereby improving the clearance rate of the protein-bound toxin; at the same time, with the ultra-high cross-linked styrene-divinylbenzene resin as the carrier, the ultra-high cross-linked styrene-divinylbenzene resin has a rich pore structure, which can adsorb medium and large molecular substances and small molecular protein-bound toxins in uremic toxins, and the polyethyleneimine immobilized on the ultra-high cross-linked styrene-divinylbenzene resin has a positive charge, which can electrostatically bind to the free protein-bound toxins in the blood to remove the protein-bound toxins. The protein-bound toxin adsorbent described in the present invention makes the protein-bound toxin in a free state through the action of the adsorption ligand, and at the same time, through the adsorption effect of the ultra-high cross-linked styrene-divinylbenzene resin and the electrostatic binding effect of the polyethyleneimine, the free protein-bound toxins are removed, thereby improving the clearance rate of the protein-bound toxins.

The preparation method of the protein-bound toxin adsorbent of the present invention comprises the following steps: firstly preparing a low-crosslinked styrene-divinylbenzene copolymer by suspension polymerization, and then preparing an ultra-high crosslinked ethylene-divinylbenzene resin by the low-crosslinked styrene-divinylbenzene copolymer, so that the ultra-high crosslinked ethylene-divinylbenzene resin has a rich pore structure and can adsorb medium and macromolecular substances and small molecular protein-bound toxins in uremic toxins; and adding polyethyleneimine during the crosslinking reaction of the low-crosslinked styrene-divinylbenzene copolymer, and using the chloromethyl groups generated during the reaction to immobilize the polyethyleneimine on the ultra-high crosslinked styrene-divinylbenzene resin, so as to avoid introducing other reagents or other substances, which is not only conducive to simplifying the reaction process and improving the reaction efficiency, but also can avoid affecting the adsorption performance of the ultra-high crosslinked styrene-divinylbenzene resin; and subsequently, by soaking the ultra-high crosslinked styrene-divinylbenzene resin in an adsorption ligand solution, the adsorption ligand can enter the pore structure of the ultra-high crosslinked styrene-divinylbenzene resin, which is conducive to the adsorption ligand fully contacting and combining with the polyethyleneimine immobilized on the ultra-high crosslinked styrene-divinylbenzene resin, and is conducive to the combination of polyethyleneimine and the adsorption ligand. The preparation method provided by the present invention simplifies the reaction steps, has a simple preparation process, mild reaction conditions, high safety during the reaction process, low production cost, and is conducive to industrial mass production.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a process flow chart for preparing a protein-bound toxin adsorbent according to an embodiment of the present invention.

Detailed ways

In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

In addition, the terms "comprising", "including", "containing", and "having" are not restrictive, that is, other steps and other components that do not affect the results can be added. Unless otherwise specified, materials, equipment, and reagents are commercially available.

In addition, although the present invention describes the various steps in the preparation in the form of S110, S120, S130, etc., this description is only for ease of understanding, and the form of S110, S120, S130, etc. does not limit the sequence of the steps.

The first aspect of the embodiments of the present application provides a protein-bound toxin adsorbent, which uses an ultra-high cross-linked styrene-divinylbenzene resin as a carrier, on which polyethyleneimine is immobilized, and the polyethyleneimine is connected to an adsorption ligand, and the adsorption ligand includes at least one of α-methyl-4-(2-methylpropyl)phenylacetic acid, oleic acid and linoleic acid.

Among them, protein-bound toxins include hippuric acid (HA), indole-3-acetic acid (IAA), indoxyl sulfate (IS), p-cresol sulfate (PCS), and 3-carboxy-4-methyl-5-propyl-2-furanpropionic acid (CMPF). The protein-bound toxin adsorbent in this embodiment can adsorb the above-mentioned protein-bound toxins, especially IAA, IS and PCS.

Specifically, α-methyl-4-(2-methylpropyl)phenylacetic acid, also known as ibuprofen, has a π-electron conjugated structure and a carboxyl group. The carboxyl group dissociates under neutral pH conditions and carries a unit negative charge. The negatively charged carboxyl group can electrostatically interact with the positively charged group, and its benzene ring forms a hydrophobic interaction with the four leucines distributed in a ring in the middle of the cavity; and α-methyl-4-(2-methylpropyl)phenylacetic acid has the same albumin binding site as p-cresol sulfate and indoxyl sulfate. With the assistance of the hydrophobic effect and electrostatic interaction of α-methyl-4-(2-methylpropyl)phenylacetic acid, α-methyl-4-(2-methylpropyl)phenylacetic acid can compete with protein-bound toxins for adsorption on albumin, and the binding force between α-methyl-4-(2-methylpropyl)phenylacetic acid and albumin is stronger than the binding force between protein-bound toxins and albumin, thereby causing the protein-bound toxins to fall off from the albumin, making the protein-bound toxins free, making it easier for the protein-bound toxin adsorbent to adsorb the protein-bound toxins.

Oleic acid and linoleic acid also have carboxyl groups, which dissociate under neutral pH conditions and carry a unit of negative charge. The negatively charged carboxyl group can undergo electrostatic interactions with positively charged groups, and both substances have hydrophobic effects and the same albumin binding sites as cresol sulfate and indoxyl sulfate. Oleic acid and/or linoleic acid are connected to the protein-bound toxin adsorbent. With the assistance of the hydrophobic effect and electrostatic interaction of oleic acid and/or linoleic acid, the protein-bound toxins can fall off the albumin, making the protein-bound toxins free, making it easier for the protein-bound toxin adsorbent to adsorb the protein-bound toxins.

In addition, α-methyl-4-(2-methylpropyl)phenylacetic acid is highly safe for human use, can be metabolized, and has less toxic side effects; oleic acid has cis-trans isomers, has a certain effect on softening blood vessels, and also plays an important role in the metabolism of humans and animals; linoleic acid is an essential fatty acid for the human body, which can lower blood cholesterol and prevent atherosclerosis; therefore, α-methyl-4-(2-methylpropyl)phenylacetic acid, oleic acid and linoleic acid are relatively safe for use in protein-bound toxin adsorbents.

In this embodiment, ultra-high cross-linked styrene-divinylbenzene resin is prepared by cross-linking reaction of low-cross-linked styrene-divinylbenzene copolymer, polyethyleneimine is introduced during the cross-linking reaction of the low-cross-linked styrene-divinylbenzene copolymer, and the adsorption ligand is connected to the polyethyleneimine by electrostatic adsorption.

Specifically, the ultra-high cross-linked styrene-divinylbenzene resin is prepared by chloromethylation reaction and Friedel-Crafts cross-linking of low-cross-linked styrene-divinylbenzene copolymer, and polyethyleneimine is introduced in the process of chloromethylation reaction of low-cross-linked styrene-divinylbenzene copolymer, polyethyleneimine dissociates with positive charge, and adsorption ligand has negative charge, and the positive charge of polyethyleneimine and the negative charge of adsorption ligand are combined through electrostatic interaction, so that the adsorption ligand is connected to polyethyleneimine. Therefore, by covalently grafting polyethyleneimine with chloromethyl generated in the reaction process of low-cross-linked styrene-divinylbenzene copolymer, the introduction of other reagents or other substances can be avoided, and polyethyleneimine is covalently bonded to the ultra-high cross-linked styrene-divinylbenzene resin, which can improve the binding strength of polyethyleneimine immobilized on the ultra-high cross-linked styrene-divinylbenzene resin, avoid polyethyleneimine falling off, and affect the adsorption performance of ultra-high cross-linked styrene-divinylbenzene resin; in addition, the adsorption ligand is connected to polyethyleneimine by electrostatic adsorption, which is convenient for the adsorption ligand to fall off from the protein-bound toxin adsorbent and enter the blood during subsequent use, so that the adsorption ligand is bound to the protein. The toxins are competitively adsorbed, causing the protein-bound toxins to fall off from albumin, increasing the release of protein-bound toxins. On the other hand, the negatively charged adsorption ligands are connected to polyethyleneimine through electrostatic interactions. When the adsorption ligands fall off and enter the blood, they will bind to albumin under electrostatic interactions, reducing the number of free adsorption ligands in the blood. In order to maintain the stability of the electrostatic interaction, the adsorption ligands will be promoted to fall off from the protein-bound toxins, so that the electrostatic interaction and the shedding of the adsorption ligands reach a state of equilibrium, which is beneficial to further increase the release of protein-bound toxins and further improve the adsorption of free protein-bound toxins by the protein-bound toxin adsorbent.

In this embodiment, the immobilized amount of polyethyleneimine ranges from 0.1mmol/g to 1mmol/g, that is, the immobilized amount of polyethyleneimine per 1g of protein-bound toxin adsorbent is from 0.1mmol to 1mmol. Thus, an appropriate amount of adsorbent ligand can be electrostatically adsorbed, further improving the clearance rate of protein-bound toxins by the protein-bound toxin adsorbent, and at the same time, it can avoid excessive amount of adsorbent ligand being released into the blood in a short period of time, causing discomfort to the body, and reducing the safety of the protein-bound toxin adsorbent.

It should be noted that, in this embodiment, the specific numerical ranges of the crosslinking degree of the ultra-high crosslinked styrene-divinylbenzene resin and the crosslinking degree of the low crosslinked styrene-divinylbenzene copolymer are not further limited, and those skilled in the art can make adjustments according to actual conditions, as long as the crosslinking degree of the ultra-high crosslinked styrene-divinylbenzene resin can be ensured to be higher than the crosslinking degree of the low crosslinked styrene-divinylbenzene copolymer.

Most protein-bound toxins contain aromatic rings and/or indole rings, and also have ionic functional groups, which make it easy for protein-bound toxins to bind to serum albumin, forming a larger protein-bound form, resulting in a smaller free fraction of protein-bound toxins. The distribution volume of protein-bound toxins in the body is much larger than the plasma volume, making protein-bound toxins difficult to remove. The inventors of the present application have conducted an analysis based on the above-mentioned characteristics of protein-bound toxins and provided a protein-bound toxin adsorbent. The protein-bound toxin adsorbent uses ultra-high cross-linked styrene-divinylbenzene resin as a carrier, immobilized polyethyleneimine, polyethyleneimine is connected to an adsorption ligand, and the adsorption ligand has a negative charge. When the protein-bound toxin adsorbent is contacted with blood, the adsorption ligand falls off the protein-bound toxin adsorbent and enters the blood. The adsorption ligand has the same albumin binding site as p-cresol sulfate and indoxyl sulfate, and can compete with protein-bound toxins for adsorption on albumin, and the binding force of the adsorption ligand to albumin is stronger than the binding force between the protein-bound toxin and albumin. , so that the protein-bound toxins fall off from the albumin, so that the protein-bound toxins are in a free state, which is convenient for the ultra-high cross-linked styrene-divinylbenzene resin and the polyethyleneimine immobilized thereon to adsorb the protein-bound toxins, thereby improving the clearance rate of the protein-bound toxins; at the same time, with the ultra-high cross-linked styrene-divinylbenzene resin as the carrier, the ultra-high cross-linked styrene-divinylbenzene resin has a rich pore structure, which can adsorb the medium and large molecular substances and small molecular protein-bound toxins in the uremic toxins, and the polyethyleneimine immobilized on the ultra-high cross-linked styrene-divinylbenzene resin has a positive charge, which can be electrostatically bound to the free protein-bound toxins in the blood, and the protein-bound toxins are removed. In this embodiment, the protein-bound toxins are freed by the action of the adsorption ligand, and the free protein-bound toxins are removed by the adsorption of the ultra-high cross-linked styrene-divinylbenzene resin and the electrostatic binding of the polyethyleneimine, thereby improving the clearance rate of the protein-bound toxins.

FIG1 is a process flow chart for preparing a protein-bound toxin adsorbent provided in an embodiment of the present application. In conjunction with FIG1 , a second aspect of an embodiment of the present application provides a method for preparing the protein-bound toxin adsorbent described in the first aspect, comprising the following steps:

Step S110, preparing a low-crosslinked styrene-divinylbenzene copolymer.

Specifically, styrene monomers, polyvinyl crosslinking agents, porogens and initiators are suspended and polymerized in a dispersion medium to obtain a low-crosslinked styrene-divinylbenzene copolymer.

More specifically, styrene monomers, polyvinyl crosslinking agents, porogens and initiators are mixed to form an oil phase, a dispersion medium, sodium chloride and magnesium chloride are mixed to form an aqueous phase, the oil phase is added to the aqueous phase, and suspension polymerization is carried out at 50°C to 100°C under stirring. After the reaction is carried out for 10 to 20 hours, the suspension polymerization product is cleaned with water and ethanol, and dried to obtain a low-crosslinked styrene-divinylbenzene copolymer. When carrying out the suspension polymerization reaction, the temperature can be gradually increased in stages for reaction. For example, after the oil phase forms uniform droplets of a certain size in the aqueous phase, the temperature can be increased to 75°C for polymerization reaction for 5 hours, then increased to 80°C for reaction for 5 hours, then increased to 95°C to 98°C, and the reaction is continued for 6 to 8 hours before stopping the reaction.

Wherein, the styrene monomer is selected from at least one of styrene, methyl styrene, and ethyl styrene, preferably, the styrene monomer is styrene; the polyvinyl crosslinking agent is selected from at least one of divinylbenzene, divinyltoluene, divinylxylene, and divinylethylbenzene, preferably, the polyvinyl crosslinking agent is divinylbenzene. The styrene monomer accounts for 20% to 90% of the total mass of the styrene monomer and the polyvinyl crosslinking agent, and the polyvinyl crosslinking agent accounts for 10% to 80% of the total mass of the styrene monomer and the polyvinyl crosslinking agent. Therefore, by using monovinyl styrene monomers and polyvinyl crosslinking agents as reaction monomers, the styrene-divinylbenzene copolymer is partially crosslinked, which is beneficial to improve the mechanical strength of the low-crosslinked styrene-divinylbenzene copolymer and the structural stability in organic solvents.

The porogen is a mixture of at least two substances selected from aromatic hydrocarbons, alkanes, higher alcohols, higher ketones, and esters; wherein the aromatic hydrocarbons are selected from toluene and xylene; the alkanes are selected from n-heptane, 200# gasoline, and solid paraffin; the higher alcohols are selected from butanol, hexanol, cyclohexanol, isooctyl alcohol, n-octanol, and methyl isobutyl carbinol; the higher ketones are selected from methyl isobutyl ketone, 2-hexanone, diisobutyl ketone, and methyl tert-butyl ketone; the esters are selected from butyl acetate, ethyl acetate, and butyl butyrate; preferably, the porogen is toluene and methyl isobutyl carbinol. As an optional embodiment, the mass of the porogen can be 70% to 230% of the total mass of the styrene monomer and the polyvinyl crosslinking agent.

The initiator is selected from at least one of benzoyl peroxide, tert-butyl peroxy-2-ethylhexanoate, and tert-amyl peroxy-2-ethylhexanoate. Preferably, the initiator is benzoyl peroxide. As an optional embodiment, the mass of the initiator is 0.5% to 1.5% of the total mass of the styrene monomer and the polyvinyl crosslinking agent. Therefore, the use of the above initiator can effectively initiate polymerization, and the price of the initiator is relatively low.

The dispersion medium is water, and the dispersion medium contains a dispersant, which is selected from at least one of gelatin, polyvinyl alcohol, and carboxymethyl cellulose. Preferably, the dispersion medium is gelatin. As an optional embodiment, the mass of the dispersant is 0.5% to 2% of the mass of the dispersion medium. Therefore, the use of the above dispersion medium is safe and environmentally friendly, and can achieve suspension polymerization of low-crosslinked styrene-divinylbenzene copolymer.

As an optional embodiment, the mass of sodium chloride is 3% to 5% of the mass of the water phase, and the mass of magnesium chloride is 2% to 4% of the mass of the water phase. The mass of the water phase is the sum of the masses of the dispersion medium, the dispersant, the sodium chloride and the magnesium chloride.

Step S120, cross-linking the low-crosslinked styrene-divinylbenzene copolymer to prepare an ultra-high cross-linked styrene-divinylbenzene resin, wherein polyethyleneimine is immobilized on the ultra-high cross-linked styrene-divinylbenzene resin, and the polyethyleneimine is immobilized on the ultra-high cross-linked styrene-divinylbenzene resin during the cross-linking reaction of the low-crosslinked styrene-divinylbenzene copolymer.

Specifically, a low-crosslinked styrene-divinylbenzene copolymer is subjected to a chloromethylation reaction, and polyethyleneimine is added during the chloromethylation reaction to obtain a low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine; and a low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine is subjected to a Friedel-Crafts reaction to obtain an ultra-high crosslinked styrene-divinylbenzene resin.

More specifically, the preparation of a low cross-linked styrene-divinylbenzene copolymer containing polyethyleneimine comprises the following steps:

A low-crosslinked styrene-divinylbenzene copolymer is added to ethylene dichloride and swelled at room temperature to fully swell the low-crosslinked styrene-divinylbenzene copolymer. The swollen low-crosslinked styrene-divinylbenzene copolymer, chloromethyl ether and anhydrous ferric chloride are refluxed at 50° C. to 60° C. for 2 h to 4 h, and then the temperature is raised to 80° C. to 100° C. for further reflux reaction for 5 h to 24 h. Meanwhile, polyethyleneimine is added during the heating process for reaction, and the polyethyleneimine is introduced into the low-crosslinked styrene-divinylbenzene copolymer to obtain a low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine. Thus, after the low-crosslinked styrene-divinylbenzene copolymer and chloromethyl ether undergo chloromethylation reaction at 50° C. to 60° C., chloromethyl groups are introduced into the low-crosslinked styrene-divinylbenzene copolymer, and then the temperature is raised to 80° C. to 100° C., and polyethyleneimine is added during the heating process to modify the chloromethyl groups with the amine groups of the polyethyleneimine, thereby introducing the polyethyleneimine into the low-crosslinked styrene-divinylbenzene copolymer, and the chloromethylation reaction is continued during the subsequent heating process to introduce sufficient chloromethyl groups into the low-crosslinked styrene-divinylbenzene copolymer so that the chloromethyl groups are in excess of the polyethyleneimine; this embodiment In the example, the chloromethyl groups produced in the reaction process of the low-crosslinked styrene-divinylbenzene copolymer are covalently grafted onto polyethyleneimine, which can avoid the introduction of other reagents or other substances, and the polyethyleneimine is covalently bonded to the ultra-high crosslinked styrene-divinylbenzene resin, which can improve the binding strength of the polyethyleneimine immobilized on the ultra-high crosslinked styrene-divinylbenzene resin and avoid the polyethyleneimine from falling off and affecting the adsorption performance of the subsequently prepared ultra-high crosslinked styrene-divinylbenzene resin. On the other hand, it can ensure the introduction of sufficient chloromethyl groups to facilitate the subsequent Friedel-Crafts reaction and improve the strength and structural stability of the carrier.

Among them, the mass ratio of low cross-linked styrene-divinylbenzene copolymer and chloromethyl ether is 1:4 to 1:6, the mass ratio of low cross-linked styrene-divinylbenzene copolymer and anhydrous ferric chloride is 1:0.5 to 1:1.5; the mass ratio of low cross-linked styrene-divinylbenzene copolymer and polyethyleneimine is 20:5 to 20:20, and the molecular weight of polyethyleneimine is 200 to 10000. Therefore, by limiting the usage ratio of each substance within the above range, it is possible to ensure that a sufficient amount of chloromethyl is introduced into the low cross-linked styrene-divinylbenzene copolymer, so that part of the chloromethyl can react with polyethyleneimine, and the remaining part of the chloromethyl can undergo subsequent Friedel-Crafts reaction to form ultra-high cross-linked styrene-divinylbenzene resin. The chlorine content in the low cross-linked styrene-divinylbenzene copolymer containing polyethyleneimine in this embodiment ranges from 1% to 5%.

After obtaining a low cross-linked styrene-divinylbenzene copolymer containing polyethyleneimine, the low cross-linked styrene-divinylbenzene copolymer containing polyethyleneimine is cleaned, and then the low cross-linked styrene-divinylbenzene copolymer containing polyethyleneimine is mixed with nitrobenzene, and then allowed to swell at 35°C to 45°C for 4h to 5h, and then zinc chloride is added under stirring to make the chloromethyl group undergo a Friedel-Crafts reaction to form an ultra-high cross-linked styrene-divinylbenzene resin, wherein the Friedel-Crafts reaction temperature is 110°C to 130°C, and the reaction time is 8h to 16h. Thus, the residual chloromethyl group on the low cross-linked styrene-divinylbenzene copolymer containing polyethyleneimine undergoes a Friedel-Crafts reaction, which can improve the strength and structural stability of the ultra-high cross-linked styrene-divinylbenzene resin on the one hand, and is conducive to forming more microporous channel structures, and improving the adsorption of the ultra-high cross-linked styrene-divinylbenzene resin to small molecule protein-bound toxins. The ultra-high cross-linked styrene-divinylbenzene resin obtained in this embodiment is immobilized with polyethyleneimine, and the immobilized amount of polyethyleneimine ranges from 0.1mmol/g to 1mmol/g, that is, the immobilized amount of polyethyleneimine per 1g of protein-bound toxin adsorbent is 0.1mmol to 1mmol.

The mass of nitrobenzene is 5 to 7 times of the mass of the low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine; the mass of zinc chloride is 0.1 to 0.5 times of the mass of the low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine.

After the ultra-high cross-linked styrene-divinylbenzene resin is prepared, the method further includes: washing the ultra-high cross-linked styrene-divinylbenzene resin with ethanol until it is clarified, then washing it with dilute hydrochloric acid with a mass fraction of 5%, then extracting it with ethanol Soxhlet, and drying it to obtain purified ultra-high cross-linked styrene-divinylbenzene resin.

Step S130, soaking the ultra-high cross-linked styrene-divinylbenzene resin in the adsorption ligand solution. After the soaking, the adsorption ligand is connected to the polyethyleneimine to obtain a protein-bound toxin adsorbent.

Specifically, an ultra-high cross-linked styrene-divinylbenzene resin is immersed in an alkaline solution until the pH value of the alkaline solution remains unchanged to obtain a transformed ultra-high cross-linked styrene-divinylbenzene resin. The transformed ultra-high cross-linked styrene-divinylbenzene resin is washed and dried, and then immersed in an adsorption ligand solution. After the soaking, the resin is washed to obtain a protein-bound toxin adsorbent, wherein the mass percentage of the adsorption ligand in the adsorption ligand solution is 10% to 40%, and the volume ratio of the ultra-high cross-linked styrene-divinylbenzene resin to the adsorption ligand solution is 1:1.2 to 1:1.5. Thus, by immersing the ultra-high cross-linked styrene-divinylbenzene resin in an alkaline solution, the chloride ions on the ultra-high cross-linked styrene-divinylbenzene resin are transformed into hydroxide ions, which is beneficial to the dissociation of the polyethyleneimine on the ultra-high cross-linked styrene-divinylbenzene resin, so that the polyethyleneimine is positively charged, so that when the ultra-high cross-linked styrene-divinylbenzene resin is immersed in the adsorption ligand solution, the positively charged polyethyleneimine attracts more negatively charged adsorption ligands, and the positive charge of the polyethyleneimine is combined with the negatively charged adsorption ligand through electrostatic interaction, so that more adsorption ligands are connected to the polyethyleneimine; in addition, immersing the ultra-high cross-linked styrene-divinylbenzene resin in the adsorption ligand solution can make the adsorption ligand enter the pore structure of the ultra-high cross-linked styrene-divinylbenzene resin, which is beneficial for the adsorption ligand to fully contact and combine with the polyethyleneimine immobilized on the ultra-high cross-linked styrene-divinylbenzene resin, and is beneficial to increase the amount of adsorption ligands on the ultra-high cross-linked styrene-divinylbenzene resin.

The alkaline solution is a NaOH solution, and the concentration of the NaOH solution is 0.1 mol/L. The transformed ultra-high cross-linked styrene-divinylbenzene resin is soaked in the adsorption ligand solution for 24 to 30 hours to allow the adsorption ligand to fully contact the polyethyleneimine immobilized on the ultra-high cross-linked styrene-divinylbenzene resin. Preferably, when the transformed ultra-high cross-linked styrene-divinylbenzene resin is soaked in the adsorption ligand solution, the adsorption ligand solution can be stirred, and the method of stirring and soaking is conducive to the combination of the adsorption ligand and the polyethyleneimine on the ultra-high cross-linked styrene-divinylbenzene resin.

In this embodiment, the transformed ultra-high cross-linked styrene-divinylbenzene resin is cleaned with deionized water to avoid affecting the activity of the groups on the ultra-high cross-linked styrene-divinylbenzene resin and avoid changes in acidity and alkalinity that affect the dissociation of polyethyleneimine on the ultra-high cross-linked styrene-divinylbenzene resin.

After the ultra-high cross-linked styrene-divinylbenzene resin is soaked in the adsorption ligand solution, it is washed with deionized water to obtain a protein-bound toxin adsorbent. The use of deionized water for washing can avoid affecting the binding of the adsorption ligand and polyethyleneimine, and avoid the adsorption ligand falling off from the polyethyleneimine, which is beneficial to ensure the structural stability of the protein-bound toxin adsorbent.

The preparation method of the protein-bound toxin adsorbent provided in this embodiment is to first prepare a low-crosslinked styrene-divinylbenzene copolymer by suspension polymerization, and then prepare an ultra-high cross-linked ethylene-divinylbenzene resin by the low-crosslinked styrene-divinylbenzene copolymer, so that the ultra-high cross-linked ethylene-divinylbenzene resin has a rich pore structure and can adsorb medium and large molecular substances and small molecular protein-bound toxins in uremic toxins, and add polyethyleneimine during the cross-linking reaction of the low-crosslinked styrene-divinylbenzene copolymer, and use the chloromethyl groups generated during the reaction to immobilize the polyethyleneimine on the ultra-high cross-linked styrene-divinylbenzene resin, which can avoid the introduction of other reagents or other substances, which is not only conducive to simplifying the reaction process and improving the reaction efficiency, but also can avoid affecting the adsorption performance of the ultra-high cross-linked styrene-divinylbenzene resin; subsequently, by immersing the ultra-high cross-linked styrene-divinylbenzene resin in an adsorption ligand solution, the adsorption ligand can enter the pore structure of the ultra-high cross-linked styrene-divinylbenzene resin, which is conducive to the adsorption ligand and the polyethyleneimine immobilized on the ultra-high cross-linked styrene-divinylbenzene resin Full contact and combination, which is conducive to the combination of polyethyleneimine and the adsorption ligand. The preparation method provided in this embodiment simplifies the reaction steps, has a simple preparation process, mild reaction conditions, high safety during the reaction process, low production cost, and is conducive to industrial mass production.

The third aspect of the present application provides a blood perfusion device, which includes the protein-bound toxin adsorbent as described above, or includes the protein-bound toxin adsorbent prepared by the preparation method of the protein-bound toxin adsorbent as described above. The protein-bound toxin adsorbent provided by the present application is used as the adsorption material of the blood perfusion device, which can effectively remove the protein-bound toxins in the blood of uremic patients during blood perfusion, and the protein-bound toxin adsorbent is used in vitro and will not enter the body, so it has low harmful effects on the human body.

In order to further explain the present invention in detail, the present invention will be further explained in conjunction with specific examples. The experimental methods used in the examples of the present invention are all conventional methods unless otherwise specified; the materials, reagents, etc. used in the examples of the present invention are all purchased from the market unless otherwise specified.

Example 1

This embodiment provides a method for preparing a protein-bound toxin adsorbent, comprising the following steps:

(1) Add 600 mL of an aqueous solution containing 2 wt% gelatin into a 1000 mL three-necked flask, stir at 50° C. for 2 h, and wait until the dispersant gelatin is completely dissolved. Then, add 15 g of sodium chloride and 10 g of magnesium chloride in sequence and stir until they are completely dissolved to obtain an aqueous phase; mix 42 g of styrene, 8 g of divinylbenzene (DVB), 50 g of toluene, 0.5 g of benzoyl peroxide, and 56 g of methyl isobutyl carbinol (MIBC) to form an oil phase, slowly add the oil phase into the aqueous phase, raise the temperature to 75° C. for reaction for 5 h, raise the temperature to 80° C. for reaction for 5 h, and then raise the temperature to 95° C. to 98° C. for insulation for 6 h to 8 h, perform suspension polymerization to crosslink and solidify the styrene-divinylbenzene copolymer, and evaporate toluene. After the reaction is completed, wash the reaction product with water and ethanol several times in sequence, filter, dry, and sieve to select a resin with a particle size of 0.6 mm to 1.2 mm, thereby obtaining a low-crosslinked styrene-divinylbenzene copolymer.

(2) Add 20 g of low-crosslinked styrene-divinylbenzene copolymer to a 500 mL three-necked flask, add 500 mL of ethylene dichloride, and let stand at room temperature for 12 h to fully swell; add 100 g of chloromethyl ether and 10 g of anhydrous ferric chloride to the swollen low-crosslinked styrene-divinylbenzene copolymer in sequence, start the stirrer, raise the temperature to 50°C and reflux for 3 h, then raise the temperature to 80°C and continue to react for 7 h, then add 5 g of polyethyleneimine, continue to react at 80°C for 14 h, cool to room temperature after the reaction is completed, filter out the mother liquor, extract with methanol for 12 h, wash with water until there is no methanol smell, filter with suction, and dry to obtain a low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine.

(3) 20 g of a low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine was added to 140 g of nitrobenzene, and the mixture was allowed to swell at 40° C. for 4 h. Under mechanical stirring, 8 g of zinc chloride was added, and the mixture was heated at 120° C. for 8 h. The chloromethyl groups underwent a Friedel-Crafts reaction to form an ultra-high crosslinked network. After the reaction was completed, the mixture was cooled to room temperature, the mother liquor was filtered out, and the mixture was washed with ethanol until clear. The mixture was then washed with 5% dilute hydrochloric acid for 8 h, extracted with ethanol for 8 h, and dried to obtain an ultra-high crosslinked styrene-divinylbenzene resin on which polyethyleneimine was immobilized.

(4) Take 20 g of the purified ultra-high cross-linked styrene-divinylbenzene resin and soak it in 100 ml of 0.1 mol/L NaOH solution. Replace the NaOH solution every 2 hours until the pH value of the solution remains unchanged to obtain the transformed ultra-high cross-linked styrene-divinylbenzene resin. Wash the transformed ultra-high cross-linked styrene-divinylbenzene resin with deionized water. After draining, soak the transformed ultra-high cross-linked styrene-divinylbenzene resin in 20 wt% ibuprofen solution for 24 hours. After soaking, wash it with deionized water 5 times to obtain a protein-bound toxin adsorbent.

Example 2

This embodiment provides a method for preparing a protein-bound toxin adsorbent, comprising the following steps:

(1) Add 600 mL of an aqueous solution containing 2 wt% gelatin into a 1000 mL three-necked flask, stir at 50° C. for 2 h, and wait until the dispersant gelatin is completely dissolved. Then, add 15 g of sodium chloride and 10 g of magnesium chloride in sequence and stir until they are completely dissolved to obtain an aqueous phase; mix 40 g of styrene, 10 g of divinylbenzene (DVB), 50 g of toluene, 0.5 g of benzoyl peroxide, and 56 g of methyl isobutyl carbinol (MIBC) to form an oil phase, slowly add the oil phase into the aqueous phase, raise the temperature to 75° C. for reaction for 5 h, raise the temperature to 80° C. for reaction for 5 h, and then raise the temperature to 95° C. to 98° C. for insulation for 6 h to 8 h, perform suspension polymerization to crosslink and solidify the styrene-divinylbenzene copolymer, and evaporate toluene. After the reaction is completed, wash the reaction product with water and ethanol several times in sequence, filter, dry, and sieve to select a resin with a particle size of 0.6 mm to 1.2 mm, thereby obtaining a low-crosslinked styrene-divinylbenzene copolymer.

(2) Add 20 g of low-crosslinked styrene-divinylbenzene copolymer to a 500 mL three-necked flask, add 500 mL of ethylene dichloride, and let stand at room temperature for 12 h to fully swell; add 100 g of chloromethyl ether and 10 g of anhydrous ferric chloride to the swollen low-crosslinked styrene-divinylbenzene copolymer in sequence, start the stirrer, raise the temperature to 50°C and reflux for 3 h, then raise the temperature to 80°C and continue to react for 7 h, then add 10 g of polyethyleneimine, continue to react at 80°C for 14 h, cool to room temperature after the reaction is completed, filter out the mother liquor, extract with methanol for 12 h, wash with water until there is no methanol smell, filter with suction, and dry to obtain a low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine.

(3) 20 g of a low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine was added to 140 g of nitrobenzene, and the mixture was allowed to swell at 40° C. for 4 h. Under mechanical stirring, 8 g of zinc chloride was added, and the mixture was heated at 120° C. for 8 h. The chloromethyl groups underwent a Friedel-Crafts reaction to form an ultra-high crosslinked network. After the reaction was completed, the mixture was cooled to room temperature, the mother liquor was filtered out, and the mixture was washed with ethanol until clear. The mixture was then washed with 5% dilute hydrochloric acid for 8 h, extracted with ethanol for 8 h, and dried to obtain an ultra-high crosslinked styrene-divinylbenzene resin on which polyethyleneimine was immobilized.

(4) Take 20 g of the purified ultra-high cross-linked styrene-divinylbenzene resin and soak it in 100 ml of 0.1 mol/L NaOH solution, replace the NaOH solution every 2 hours until the pH value of the solution remains unchanged, and obtain the transformed ultra-high cross-linked styrene-divinylbenzene resin. The transformed ultra-high cross-linked styrene-divinylbenzene resin is thoroughly washed with deionized water, drained, and then soaked in 30 wt% ibuprofen solution for 24 hours. After the soaking, wash it with deionized water 5 times to obtain a protein-bound toxin adsorbent.

Comparative Example 1

The ultra-high cross-linked styrene-divinylbenzene resin immobilized with polyethyleneimine prepared in step (3) of Example 1 was used as the adsorbent in Comparative Example 1.

Comparative Example 2

The adsorbent in the commercially available HA130 hemoperfusion device produced by Jianfan Biotechnology Group Co., Ltd. was used as the adsorbent in Comparative Example 2.

Adsorption performance test: A protein-bound toxin-plasma solution containing an initial concentration of IS of 2.5 mg/L, a protein-bound toxin-plasma solution containing an initial concentration of PCS of 2.5 mg/L, and a protein-bound toxin-plasma solution containing an initial concentration of IAA of 0.5 mg/L were prepared by an external addition method; 1 mL of the protein-bound toxin adsorbent prepared in Example 1 and Example 2, and 1 mL of the adsorbent in Comparative Example 1 and Comparative Example 2 were taken, respectively, and added to 10 mL of the above three protein-bound toxin-plasma solutions, and oscillated at a rate of 110 r/min in a constant temperature oscillator at 37°C for 2 h for adsorption. After that, the concentrations of different protein-bound toxins before and after adsorption were detected, and the adsorption rates of different adsorbents for different protein-bound toxins were calculated (for example: when calculating the adsorption rate for IS, 1 mL of the protein-bound toxin adsorbents prepared in Example 1 and Example 2, and 1 mL of the adsorbents in Comparative Examples 1 and 2 were taken, and 10 mL of protein-bound toxin-plasma solution containing an initial IS concentration of 2.5 mg/L was added, respectively, and adsorbed at a rate of 110 r/min in a constant temperature oscillator at 37°C for 2 hours, and then the concentrations of IS before and after adsorption were detected, and the adsorption rates of different adsorbents for IS were calculated). Wherein, the concentrations of IS, PCS and IAA were detected by HPLC analysis method,

The calculation formula of adsorption rate is: Cr (%) = (C0-Ct) / C0 × 100%, where Cr is the concentration decrease rate of the target protein-bound toxin, C0 is the detection concentration of the target protein-bound toxin before adsorption, and Ct is the detection concentration of the target protein-bound toxin after 2 hours of adsorption. The adsorption rates of the adsorbents in each embodiment, comparative example 1 and comparative example 2 for each protein-bound toxin are shown in Table 1.

Table 1

As can be seen from Table 1, the protein-bound toxin adsorbents in Example 1 and Example 2 have significantly improved adsorption performance for IS, PCS and IAA compared to the adsorbents in Comparative Examples 1 and 2, indicating that the protein-bound toxin adsorbent provided in the present invention has a better removal effect on protein-bound toxins, especially for IS, PCS and IAA. In addition, the protein-bound toxin adsorbent provided by the present invention also has good safety performance and excellent mechanical strength, and can meet the needs of whole blood perfusion.

Although the disclosure is disclosed as above, the protection scope of the disclosure is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the disclosure, and these changes and modifications will fall within the protection scope of the present invention.

Claims (10)

1. A protein-bound toxin adsorbent, characterized in that the protein-bound toxin adsorbent uses ultra-high cross-linked styrene-divinylbenzene resin as a carrier, polyethyleneimine is immobilized on the carrier, and the polyethyleneimine is connected to an adsorption ligand, and the adsorption ligand includes at least one of α-methyl-4-(2-methylpropyl)phenylacetic acid, oleic acid and linoleic acid. 2. The protein-bound toxin adsorbent according to claim 1 is characterized in that the ultra-high cross-linked styrene-divinylbenzene resin is prepared by cross-linking reaction of low-cross-linked styrene-divinylbenzene copolymer, the polyethyleneimine is introduced during the cross-linking reaction of the low-cross-linked styrene-divinylbenzene copolymer, the adsorption ligand is connected to the polyethyleneimine by electrostatic adsorption, and the solid loading range of the polyethyleneimine is 0.1 mmol/g to 1 mmol/g. 3. A method for preparing a protein-bound toxin adsorbent, characterized in that it is used to prepare the protein-bound toxin adsorbent as claimed in claim 1 or 2, and the preparation method comprises: Preparation of low cross-linked styrene-divinylbenzene copolymers; The low-crosslinked styrene-divinylbenzene copolymer undergoes a crosslinking reaction to prepare an ultra-high crosslinked styrene-divinylbenzene resin, wherein polyethyleneimine is immobilized on the ultra-high crosslinked styrene-divinylbenzene resin, and the polyethyleneimine is immobilized on the ultra-high crosslinked styrene-divinylbenzene resin during the crosslinking reaction of the low-crosslinked styrene-divinylbenzene copolymer; The ultra-high cross-linked styrene-divinylbenzene resin is soaked in an adsorption ligand solution. After the soaking is completed, the adsorption ligand is connected to the polyethyleneimine to obtain a protein-bound toxin adsorbent. 4. The method for preparing a protein-bound toxin adsorbent according to claim 3, characterized in that the low-crosslinked styrene-divinylbenzene copolymer is cross-linked to prepare an ultra-high crosslinked styrene-divinylbenzene resin, comprising: The low-crosslinked styrene-divinylbenzene copolymer is subjected to a chloromethylation reaction, and polyethyleneimine is added during the chloromethylation reaction to obtain a low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine; The low cross-linked styrene-divinylbenzene copolymer containing polyethyleneimine is subjected to Friedel-Crafts reaction to obtain an ultra-high cross-linked styrene-divinylbenzene resin. 5. The method for preparing a protein-bound toxin adsorbent according to claim 4, characterized in that the low-crosslinked styrene-divinylbenzene copolymer is subjected to a chloromethylation reaction, and polyethyleneimine is added during the chloromethylation reaction to obtain a low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine, comprising: After a low-crosslinked styrene-divinylbenzene copolymer is added to ethylene dichloride for swelling, the swollen low-crosslinked styrene-divinylbenzene copolymer, chloromethyl ether and anhydrous ferric chloride are refluxed at 50° C. to 60° C. for 2 h to 4 h, and then the temperature is raised to 80° C. to 100° C. for further reflux reaction for 5 h to 24 h. Meanwhile, polyethyleneimine is added during the heating process for reaction, and the polyethyleneimine is introduced into the low-crosslinked styrene-divinylbenzene copolymer to obtain a low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine. 6. The method for preparing a protein-bound toxin adsorbent according to claim 5, characterized in that the mass ratio of the low-crosslinked styrene-divinylbenzene copolymer to the chloromethyl ether is 1:4 to 1:6, the mass ratio of the low-crosslinked styrene-divinylbenzene copolymer to the anhydrous ferric chloride is 1:0.5 to 1:1.5; the mass ratio of the low-crosslinked styrene-divinylbenzene copolymer to the polyethyleneimine is 20:5 to 20:20. 7. The method for preparing a protein-bound toxin adsorbent according to claim 4, characterized in that the step of subjecting the low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine to a Friedel-Crafts reaction to obtain an ultra-high crosslinked styrene-divinylbenzene resin comprises: The low-crosslinked styrene-divinylbenzene copolymer containing polyethyleneimine and nitrobenzene are mixed, and then allowed to stand at 35° C. to 45° C. for 4 to 5 hours, and then zinc chloride is added under stirring to carry out Friedel-Crafts reaction to form an ultra-high crosslinked styrene-divinylbenzene resin, wherein the temperature of the Friedel-Crafts reaction is 110° C. to 130° C., and the reaction time is 8 to 16 hours. 8. The method for preparing a protein-bound toxin adsorbent according to claim 3, characterized in that the ultra-high cross-linked styrene-divinylbenzene resin is soaked in an adsorption ligand solution, and after the soaking, the adsorption ligand is connected to the polyethyleneimine to obtain the protein-bound toxin adsorbent, comprising: The ultra-high cross-linked styrene-divinylbenzene resin is immersed in an alkaline solution until the pH value of the alkaline solution remains unchanged to obtain the transformed ultra-high cross-linked styrene-divinylbenzene resin; the transformed ultra-high cross-linked styrene-divinylbenzene resin is washed and dried, and then immersed in an adsorption ligand solution; after the soaking, the resin is washed to obtain a protein-bound toxin adsorbent, wherein the mass percentage of the adsorption ligand in the adsorption ligand solution is 10% to 40%. 9. The method for preparing a protein-bound toxin adsorbent according to claim 8 is characterized in that the transformed ultra-high cross-linked styrene-divinylbenzene resin is washed with deionized water, and after the ultra-high cross-linked styrene-divinylbenzene resin is soaked in the adsorption ligand, it is washed with deionized water. 10. A blood perfusion device, characterized in that it comprises the protein-bound toxin adsorbent according to claim 1 or 2, or the protein-bound toxin adsorbent prepared by the preparation method according to any one of claims 3 to 9.