CN109485628B - Chiral polyamide membrane and preparation method and application thereof - Google Patents

Abstract

The invention discloses a chiral polyamide membrane and its preparation method and application in the separation of chiral drugs. The chiral polyamide membrane is based on a cellulose acetate membrane, and a chiral resolving agent ethylenediamine-β-cyclodextrin is immobilized on the surface of the chiral polyamide membrane through a linking agent trimesyl chloride. The specific preparation method is that β-cyclodextrin is separately prepared with p-toluenesulfonyl chloride and anhydrous ethylenediamine by a two-step synthesis method to obtain ethylenediamine-modified-β-cyclodextrin, which is used as a chiral selector to mechanically The commercial cellulose acetate material with high strength, strong compression resistance, good chemical stability and low price is used as the base film material, and trimesyl chloride is selected as the linking agent. Interfacial Polyamide Cellulose Acetate Membrane for Splitting Capability. The chiral polyamide membrane of the invention has the advantages of low cost, simple preparation process and wide separation objects.

Description

A kind of chiral polyamide membrane and its preparation method and application

technical field

The invention belongs to the technical field of chiral separation, and in particular relates to a chiral polyamide membrane and a preparation method thereof and application in the separation of chiral drugs.

Background technique

Membrane technology separation method is to use the specific separation function sites contained in the membrane or outside the membrane to separate the vortex mixture. The membrane technology splitting method has the advantages of low energy consumption, simple operation, large batch volume, easy continuous operation, easy industrial scale-up, flexible device design and system application, and room temperature operation in most cases.

According to the shape of the membrane, the membrane technology splitting method is divided into two types: liquid membrane splitting method and solid membrane splitting method. Chiral liquid membranes have a common disadvantage that is difficult to overcome, that is, poor stability, and their industrial applications have been greatly limited. Chiral separation has good stability of solid membrane, so it has become the key research direction of chiral separation by membrane method.

Chiral solid films can be divided into three types: bulk solid films, modified solid films, and molecularly imprinted solid films according to the characteristics of the film material and the preparation process. The body solid film has less film material, and the use surface is narrow. Molecularly imprinted membranes have strong specificity, each molecularly imprinted membrane can only resolve one chiral substance, and the preparation process is complicated. The modified solid film has good designability, high separation efficiency and wide application, which has become the key research direction of chiral separation solid film. Su Cailian et al. used alumina ceramic film as passivation support and β-CD as a solid film as a chiral selector. The split object was D,L,-phenylalanine, D-phenylalanine and L-benzene After alanine was filtered by membrane, it was judged by UV that it intercepted the two configurations; the flow difference was used to preliminarily determine that the prepared membrane had a splitting effect on phenylalanine (Su Cailian, Dai Rongji, Tong Bin. Cyclodextrin modified Separation of Amino Acid Enantiomers by Ceramic Tube Membrane. Proceedings of the Second Conference on Membrane Science and Technology Report. 2005, 09). Dai Rongji et al. used β-cyclodextrin as the chiral selector, ceramic membrane as the base membrane material, and epichlorohydrin as the crosslinking agent to split 1-methyl-6,7-dihydroxy-1,2, The chiral recognition ability of the membrane prepared by 3,4,-tetrahydroisoquinoline gradually decreased with the prolongation of permeation time, and the equilibrium was reached after about 9 hours. The ratio of β-cyclodextrin was changed from 0.87 to 1.55 (Dai Rongji, Su Cailian, Wu Haiyan, Deng Yulin. β-cyclodextrin chiral membrane separation of 1-methyl-6,7-dihydroxy-1,2,3,4 , - Tetrahydroisoquinoline. 2008, 06; Journal of Beijing Institute of Technology). Liu Shen et al. used β-CD as a chiral selector, and used cellulose acetate (CA) and sodium alginate (SA) as base film materials, respectively, to prepare CA/β-CD and SA/β-CD chiral membranes by blending method. Sexual membrane. Chiral separation by blending α-CD, benzyl cyclodextrin, cyclodextrin p-toluenesulfonate, cyclodextrin water-soluble oligomers, and 2,4-dimethyl β-CD with cellulose acetate Membrane, the separation rates of tryptophan enantiomers were 6.57%, 7.58%, 7.85%, 8.02%, 8.59%, and the separation rates of phenylalanine enantiomers were 7.68%, 9.33%, 9.07%, 9.57%, respectively , 9.85%. The chemically cross-linked membrane was obtained by the reaction of CA and β-CD, and the tryptophan and phenylalanine were separated. The maximum separation rate reached 9.9% and 10.9%, respectively. (Liu Shen, Jin Zhimin, Wu Liguang; Master's thesis on the preparation of chiral membranes based on β-cyclodextrin and their separation of tryptophan and phenylalanine enantiomers, Zhejiang University of Technology; June 2013).

In general, existing resolving agents exist difficult problems such as high preparation cost and harsh conditions, which restrict the rapid development of the separation field all the time.

SUMMARY OF THE INVENTION

The object of the present invention is to solve the problems of high energy consumption, low efficiency and large pollution of the chiral drug separation method, and to provide a chiral polyamide membrane and its preparation method and application in the separation of chiral drugs. Diamine-β-cyclodextrin is used as a chiral resolving agent, cellulose acetate is used as a base film material, and trimesic acid chloride is used as a linking agent, and a chiral resolving agent with low cost, simple preparation process and wide range of resolution objects can be prepared. The chiral separation solid film has excellent effect on the chiral separation of warfarin and tryptophan.

In order to solve the above problems, the technical scheme adopted in the present invention is as follows:

A chiral polyamide membrane is made of cellulose acetate membrane as a base membrane, and a chiral resolving agent ethylenediamine-β-cyclodextrin is immobilized on its surface through a linking agent trimesyl chloride.

Further, the preparation method of the ethylenediamine-β-cyclodextrin comprises the following steps:

Step 1, add the NaOH solution to the β-cyclodextrin suspension, the mass ratio of NaOH and β-cyclodextrin is (9-12) g: (90-110) g, wait for the β-cyclodextrin to suspend After the turbid liquid becomes a clear pale yellow solution, add p-toluenesulfonyl chloride, and the mass ratio of p-toluenesulfonyl chloride to β-cyclodextrin is (16-18) g: (90-110) g;

In step 2, the reaction system obtained in step 1 was stirred for 2-3 hours, adjusted to pH 7.0 with 2 mol·L ^-1 hydrochloric acid, placed at 4°C for reaction for 12 hours, and the filter cake was immersed in acetone for 24 hours after suction filtration;

Step 3, removing acetone, adding water to the crude reaction product, recrystallization, suction filtration, and vacuum drying the filter cake at 50-70°C for 12h to obtain mono-6-toluenesulfonyl-β-cyclodextrin;

Step 4, adding anhydrous ethylenediamine to mono-6-toluenesulfonyl-β-cyclodextrin, the mass ratio of mono-6-toluenesulfonyl-β-cyclodextrin to anhydrous ethylenediamine is (4 -6) g: (24-36) mL, under nitrogen protection, after heating in an oil bath at 70-80°C for 5-7 hours, the unreacted ethylenediamine was distilled off under reduced pressure, then acetone was added, suction filtration, and the filter cake was dissolved In a water/methanol solution with a volume ratio of 3:1, acetone was added, and a white precipitate was obtained by suction filtration. Repeat washing to remove residual ethylenediamine. Finally, the filter cake was vacuum-dried at 50 °C for 72 hours to obtain ethyl acetate. Diamine-beta-cyclodextrin.

The preparation method of above-mentioned chiral polyamide membrane, comprises the following steps:

Step 1: The cellulose acetate membrane is activated and pretreated. First, the commercial cellulose acetate membrane with a pore size of 0.22 μm is immersed in pure water to wash, take it out and place it in an aqueous NaOH solution, and heat it in a water bath at 25-35°C for 30-50min to make the membrane. The acetyl group on the membrane is hydrolyzed, then the membrane is taken out and rinsed with deionized water until the washing solution reaches pH 7.0;

Step 2, soaking the pretreated activated cellulose acetate film in 0.3-0.5wt.% trimesyl chloride n-hexane for 20-24 h, and soaking it in a solution containing 0.3-0.8wt.% ethylenediamine-β after taking out -In the aqueous solution of cyclodextrin and 0.1wt.% triethylamine for 20-24h, after taking it out, immerse it again in 0.5wt.% trimesyl chloride n-hexane for 1min, then carry out curing treatment, and finally take out and rinse with pure water to remove Solvent remained on the surface to obtain a chiral polyamide film.

Further, the mass fraction of the aqueous solution of NaOH in step 1 is 0.2-0.4%.

Further, in step 2, the curing temperature is 50°C to 70°C, and the curing time is 5 to 20 minutes.

The application of the above-mentioned chiral polyamide membrane in the separation of chiral drugs.

The application of the above-mentioned chiral polyamide membrane in the resolution of chiral drug warfarin.

The application of the above-mentioned chiral polyamide membrane in the separation of chiral drug tryptophan.

Compared with the prior art, the beneficial effects of the present invention are:

1, the present invention adopts acetone as organic solvent in the preparation process of intermediate product single 6-toluenesulfonyl-β-cyclodextrin, removes unreacted p-toluenesulfonyl chloride in the crude product, and overcomes the problems in existing purification methods. The disadvantage of taking a long time.

2. Using ethylenediamine-β-cyclodextrin as the chiral resolving agent, cellulose acetate as the base film material, and trimesic acid chloride as the linking agent, it can be prepared with low cost, simple preparation process, and separation object. A wide range of chiral split solid films;

3. The chiral polyamide membrane prepared by the present invention can split the enantiomers of warfarin and tryptophan, and is less affected by the environment during the splitting of the membrane, and has good stability.

4. The chiral polyamide membrane prepared by the present invention can tolerate a wide range of pH, and the pH tolerance range is 3-9.

Description of drawings

FIG. 1 is a schematic diagram of the preparation process and structure of the chiral polyamide membrane of the present invention.

FIG. 2 is a surface electron microscope image of the cellulose acetate film and the prepared chiral polyamide film in Example 1. FIG.

3 is a cross-sectional electron microscope view of the cellulose acetate film and the prepared chiral polyamide film in Example 1.

FIG. 4 is the resolution stability result of the chiral polyamide film prepared in Example 1. FIG.

Figure 5 shows the pH tolerance results of the chiral polyamide membrane prepared in Example 2, wherein Sample is the test group and Control is the blank group.

Figure 6 is a graph showing the results of the separation of the chiral polyamide membranes prepared in Example 3 on different drugs at different pH values (a. Nefopam, b. Ketoprofen, c. Ibuprofen, d. China Farin), wherein Permeate is the filtrate and Feed is the stock solution.

Detailed ways

The present invention will be further described below with reference to specific embodiments.

The process and schematic diagram of the preparation of the chiral polyamide membrane in the present invention are shown in FIG. 1 .

Example 1

First, an ethylenediamine-β-cyclodextrin chiral polyamide membrane was prepared by the following steps, and then the concentration ratio of the two configurations in the filtrate filtered by the chiral membrane and the The concentration ratio of the two configurations in the stock solution was used to evaluate the resolution performance.

Synthesis of ethylenediamine-β-cyclodextrin:

The recrystallized β-cyclodextrin (100 g, 88 mmol) was weighed into a 1000 mL beaker containing 833 mL of purified water. NaOH (10.95g, 0.27mol) was dissolved in 33mL of water, and added dropwise to the above suspension within 10min under magnetic stirring conditions. After the dropwise addition was completed, the suspension became a uniform and slightly yellow solution. Weigh p-toluenesulfonyl chloride (p-TsCl, 16.82 g, 0.09 mol) and dissolve it in 50 mL of acetonitrile, and add the solution dropwise to the light yellow reaction solution containing β-cyclodextrin. A large amount of white precipitate formed. Vigorously stirred at 25°C, and after 2.5 h, 2 mol/L HCl aqueous solution was added dropwise to the reaction solution to reduce the pH to near neutrality. Then, the suspension was placed in a 4°C refrigerator overnight. Suction filtration was carried out the next day, and the filter cake was immersed in acetone to remove residual p-TsCl. After 24 hours, the acetone was removed, and the filter cake was recrystallized with water. Finally, the filter cake was vacuum-dried at 70 °C overnight to obtain a white single 6 -Tosyl-β-cyclodextrin product. Weigh 5g of mono-6-toluenesulfonyl-β-cyclodextrin into a 100mL round-bottomed flask, then add 30mL of anhydrous ethylenediamine, under nitrogen protection, heat in an oil bath at 75°C, the reaction ends after 6h, and evaporated under reduced pressure. The unreacted ethylenediamine was removed until the reaction solution was syrupy, and the reaction product was cooled to room temperature. Then add 250 mL of acetone, filter with suction, dissolve the filter cake in a solution of 60 mL of water/methanol (3:1, V/V), then add 250 mL of acetone, and filter with suction to obtain a white precipitate. Repeat this several times to remove residual of ethylenediamine. Finally, the filter cake was vacuum dried at 50 °C for 72 h to obtain the final product.

Preparation of ethylenediamine-β-cyclodextrin chiral polyamide membrane composite membrane:

(1) Activation pretreatment of cellulose acetate membrane: first immerse a commercial cellulose acetate membrane with a pore size of 0.22 μm in pure water and wash it, then take out the filter membrane, put it in an aqueous solution of NaOH, and heat it in a 35°C water bath for 40 minutes to make the membrane The acetyl group on it is hydrolyzed. The membrane was then removed and rinsed 5 times with deionized water until the wash was neutral.

(2) Soak the pretreated activated cellulose film in 0.5wt.% trimesic acid chloride (TMC) n-hexane, after 24 hours, take it out and soak it in ethylenediamine-β-containing 0.3wt.% The aqueous solution of cyclodextrin and 0.1wt.% triethylamine (TEA), after 24 hours, was finally immersed in 0.5wt.% TMC in 50 mL of n-hexane solution for 1 min, and then cured in a 60°C oven for 20 min. Repeated rinsing with purified water to remove residual solvent on the surface, and stored in deionized water at 4°C for later use.

Performance characterization:

The cellulose acetate membrane and the chiral polyamide composite membrane were observed by scanning electron microscopy, as shown in Figure 2 and Figure 3. The two electron micrographs in Fig. 2 are from left to right, and are the surface electron micrographs of the unmodified ethylenediamine-β-cyclodextrin cellulose acetate film and the chiral polyamide film, respectively, with a magnification of 2000 times. The two electron micrographs in Fig. 3, from left to right, cross-sectional electron micrographs of unmodified ethylenediamine-β-cyclodextrin cellulose acetate film and chiral polyamide cellulose film, both at 2000x magnification .

It can be seen from the figure that the chiral polyamide cellulose membrane modified with ethylenediamine-β-cyclodextrin has less pore size, indicating that ethylenediamine-β-cyclodextrin is cross-linked by trimesyl chloride immobilized on the membrane.

Membrane splitting stability evaluation:

The concentration of tryptophan stock solution is 0.025g/L, the filtration flow rate is 0.1mL/min, the pH value of tryptophan solution is 6.5, and the filtration temperature is 25℃; the chiral membrane is filtered for 12h, and the collector is changed every 2h to collect the filtrate, and the HPLC method is used for detection. Resolution stability of chiral membranes within 12 h. It can be seen from Figure 4 that the prepared chiral polyamide membrane has a stable chiral resolution effect within 12 hours, and RSD=4.8%.

Intra-membrane and inter-membrane precision:

Four batches of chiral polyamide membranes were prepared, and the tryptophan solution was filtered through 8 layers of chiral membranes each time under the optimal resolution conditions. The e.e% of the filtrate was detected by HPLC. The resolution precision between different batches of prepared chiral polyamide membranes was investigated. The inter-membrane resolution precision is shown in the table below:

Table 1 Intermembrane precision

It can be seen from the above table that the chiral resolution effect of the prepared chiral polyamide membrane is stable.

Example 2

A preparation method of ethylenediamine-β-cyclodextrin, comprising the following steps:

(1) Weigh recrystallized β-cyclodextrin (90 g, 79 mmol) and add it to a 1000 mL beaker containing 800 mL of purified water, dissolve NaOH (10 g, 0.25 mol) in 30 mL of water, under magnetic stirring conditions, in be added dropwise to the above-mentioned suspension within 8min;

(2) After the β-cyclodextrin suspension becomes a clear pale yellow solution, weigh p-toluenesulfonyl chloride (p-TsCl, 16 g, 0.086 mol) and dissolve it in 45 mL of acetonitrile, and add the solution dropwise to the above-mentioned solution containing In the light yellow reaction solution of β-cyclodextrin, after 70 minutes, all the dropwise additions were completed, and a large amount of white precipitates were formed;

(3) The above reaction system was vigorously stirred at room temperature for 2 hours, then adjusted to near neutrality with 2 mol·L ^-1 hydrochloric acid, and placed in a refrigerator at 4°C overnight; the next day, suction filtered, and the filter cake was immersed in acetone.

(5) After 22 hours, remove acetone, add water to the crude reaction product, recrystallize the filter cake with water, filter to obtain a filtrate, put it in a refrigerator at 4°C to precipitate the product, and filter the filter cake at 60°C with suction. Under vacuum drying conditions overnight, the mono-6-toluenesulfonyl-β-cyclodextrin product was obtained.

(6) adding anhydrous ethylenediamine into the round-bottomed flask containing mono-6-toluenesulfonyl β-cyclodextrin, the added mass of mono-6-toluenesulfonyl β-cyclodextrin is the same as that of anhydrous ethylenediamine The volume ratio is 4g:24mL, under nitrogen protection, after heating in an oil bath at 80°C for 5h, the unreacted ethylenediamine is distilled off under reduced pressure.

(7) then add 200mL acetone, suction filter, dissolve the filter cake in the solution of 50mL water/methanol (3:1, V/V), then add 200mL acetone again, suction filter to obtain white precipitate, repeat this several times, to remove residual ethylenediamine. Finally, the filter cake was vacuum dried at 50 °C for 72 h to obtain the final product

Preparation of ethylenediamine-β-cyclodextrin chiral polyamide:

(1) Activation pretreatment of cellulose acetate membrane: first immerse a commercial cellulose acetate membrane with a pore size of 0.22 μm in pure water and wash it, then take out the filter membrane, put it in an aqueous solution of NaOH, and heat it in a 30°C water bath for 50 minutes to make the membrane The acetyl group on it is hydrolyzed. The membrane was then removed and rinsed 6 times with deionized water until the wash was neutral

(2) Soak the pretreated activated cellulose film in 0.3wt.% trimesic acid chloride (TMC) n-hexane, after 22 hours, take it out and soak it in ethylenediamine-β-containing 0.5wt.% The aqueous solution of cyclodextrin and 0.1wt.% triethylamine (TEA), after 22 hours, was finally immersed in 50 mL n-hexane solution of 0.5wt.% TMC for 1min, and then cured in a 50°C oven for 30min. Finally, the film was taken out, Rinse repeatedly with purified water to remove residual solvent on the surface, and store in deionized water at 4°C for later use.

Performance characterization:

Evaluation of pH Tolerance Range of Chiral Polyamide Membranes

The buffer solution with pH values of 1, 3, 6, 9, and 11 was selected as the hydrolysis solution, and the prepared chiral polyamide membrane was put into the above-mentioned buffer solution. Enter the thermostatic oscillator at 150 rpm and shake for 24 hours, then, measure the total organic carbon (TOC) of the experimental group and the blank group respectively, and judge the performance of the membrane at different pH values by comparing the TOC values of the experimental group and the blank group. In terms of hydrolysis, it can be seen from Figure 5 that the prepared chiral polyamide membrane is stable within the pH range of 3 to 9 within 24 h.

The chiral polyamide membrane prepared in this example has a wide pH tolerance range.

Example 3

A preparation method of ethylenediamine-β-cyclodextrin, comprising the following steps:

(1) Weigh recrystallized β-cyclodextrin (110g, 96.8mmol) into a 1000mL beaker containing 850mL of purified water, dissolve NaOH (12g, 0.3mol) in 40mL of water, and under magnetic stirring conditions, Add dropwise to the above suspension within 11min;

(2) After the β-cyclodextrin suspension becomes a clear pale yellow solution, weigh p-toluenesulfonyl chloride (p-TsCl, 18 g, 0.096 mol) and dissolve it in 50 mL of acetonitrile, and add the solution dropwise to the above-mentioned solution containing In the light yellow reaction solution of β-cyclodextrin, after 80 minutes, it was completely added dropwise, and a large amount of white precipitates were formed;

(3) The above reaction system was vigorously stirred at room temperature for 3 hours, then adjusted to near neutrality with 2 mol·L ^-1 hydrochloric acid, and placed in a refrigerator at 4°C overnight; the next day, suction filtered, and the filter cake was immersed in acetone.

(5) After 30 hours, acetone was removed, water was added to the crude reaction product, the filter cake was recrystallized with water, filtered with suction, and the filter cake was vacuum-dried at 60°C overnight to obtain mono-6-toluenesulfonyl-β - Cyclodextrin products.

(6) adding anhydrous ethylenediamine into the round-bottomed flask containing mono-6-toluenesulfonyl β-cyclodextrin, the added mass of mono-6-toluenesulfonyl β-cyclodextrin is the same as that of anhydrous ethylenediamine The volume ratio is 6g:36mL, under nitrogen protection, after heating in an oil bath at 70°C for 7h, the unreacted ethylenediamine is distilled off under reduced pressure.

(7) then add 300mL acetone, suction filter, dissolve the filter cake in the solution of 70mL water/methanol (3:1, V/V), then add 300mL acetone again, suction filter to obtain white precipitate, repeat this several times, to remove residual ethylenediamine. Finally, the filter cake was vacuum dried at 50 °C for 72 h to obtain the final product

Preparation of ethylenediamine-β-cyclodextrin chiral polyamide:

(1) Activation pretreatment of cellulose acetate membrane: first immerse a commercial cellulose acetate membrane with a pore size of 0.22 μm in pure water and wash it, then take out the filter membrane, put it in an aqueous solution of NaOH, and heat it in a 35°C water bath for 40 minutes to make the membrane The acetyl group on it is hydrolyzed. The membrane was then removed and rinsed 6 times with deionized water until the wash was neutral

(2) Soak the pretreated activated cellulose film in 0.4wt.% trimesyl chloride (TMC) n-hexane, after 20 hours, take it out and soak it in ethylenediamine-β-containing 0.8wt.% The aqueous solution of cyclodextrin and 0.1 wt.% triethylamine (TEA), after 20 hours, was finally immersed in 50 mL of n-hexane solution of 0.5 wt.% TMC for 1 min, followed by curing in a 60°C oven for 20 min, and finally, the film was taken out, Rinse repeatedly with purified water to remove residual solvent on the surface, and store in deionized water at 4°C for later use.

Performance characterization:

Evaluation of Resolution of Chiral Polyamide Membranes

Select chiral drug stock solution concentration of 0.025g/L, filtration flow rate of 0.1mL/min, original solution pH values of 4, 5, and 6, respectively, and filtration temperature of 25 °C; chiral membrane filtration for 3 hours, and the filtrate is collected by changing the collector once for each filtration. , the e.e% of the filtrate and the stock solution were detected by HPLC. Figure 6 is a diagram of the separation of chiral drugs such as ibuprofen, warfarin, nefopam and ketoprofen by the chiral polyamide membrane prepared in this example. According to Figure 6, the prepared chiral polyamide The resolution e.e% of warfarin by the amide membrane was 9.7%.

Claims (3)

1. the application of chiral polyamide membrane in the splitting of chiral drug warfarin, it is characterized in that: The chiral polyamide film uses a cellulose acetate film as a base film, and the chiral resolving agent ethylenediamine-β-cyclodextrin is immobilized on its surface through a linking agent trimesyl chloride; The preparation method of the ethylenediamine-β-cyclodextrin comprises the following steps: Step 1, add the NaOH solution to the β-cyclodextrin suspension, the mass ratio of NaOH and β-cyclodextrin is (9-12) g: (90-110) g, wait for the β-cyclodextrin to suspend After the turbid liquid becomes a clear pale yellow solution, add p-toluenesulfonyl chloride, the mass ratio of p-toluenesulfonyl chloride to β-cyclodextrin is (16-18) g: (90-110) g; In step 2, the reaction system obtained in step 1 was stirred for 2-3 h, adjusted to pH 7.0 with 2 mol·L ^-1 hydrochloric acid, placed at 4°C for reaction for 12 h, and after suction filtration, the filter cake was immersed in acetone for 24 h; Step 3, removing acetone, adding water to the crude reaction product, recrystallization, suction filtration, and vacuum drying the filter cake at 50-70 °C for 12 h to obtain mono-6-toluenesulfonyl-β-cyclodextrin; Step 4, adding anhydrous ethylenediamine to mono-6-toluenesulfonyl-β-cyclodextrin, the mass ratio of mono-6-toluenesulfonyl-β-cyclodextrin to anhydrous ethylenediamine is (4 -6) g: (24-36) mL, under nitrogen protection, after heating in an oil bath at 70-80°C for 5-7 hours, the unreacted ethylenediamine was distilled off under reduced pressure, then acetone was added, and the filter cake was filtered with suction. It was dissolved in a water/methanol solution with a volume ratio of 3:1, then acetone was added, and a white precipitate was obtained by suction filtration, which was repeatedly washed to remove residual ethylenediamine. Finally, the filter cake was vacuum-dried at 50 °C for 72 h. Obtain ethylenediamine-β-cyclodextrin; The preparation method of the chiral polyamide membrane comprises the following steps: Step 1: The cellulose acetate membrane is activated and pretreated. First, the commercial cellulose acetate membrane with a pore size of 0.22 μm is immersed in pure water, washed, taken out and placed in an aqueous NaOH solution, and heated in a water bath at 25-35 °C for 30-50 min to make the membrane. The acetyl group on the membrane is hydrolyzed, then the membrane is removed and rinsed with deionized water until the washing solution reaches pH 7.0; Step 2, soak the pretreated activated cellulose acetate film in 0.3-0.5 wt.% trimesyl chloride n-hexane for 20-24 h, take it out and soak it in a solution containing 0.3-0.8 wt.% ethylenediamine-β. -In the aqueous solution of cyclodextrin and 0.1 wt.% triethylamine for 20-24 h, after taking out, immersed in 0.5 wt.% trimesyl chloride n-hexane for 1 min, then curing treatment, and finally taking out with purified water The residual solvent on the surface was removed by rinsing to obtain a chiral polyamide membrane. 2. application according to claim 1, is characterized in that: in step 1, the mass fraction of the aqueous solution of NaOH is 0.2～0.4%. 3. The application according to claim 1, characterized in that: in step 2, the curing temperature is 50°C to 70°C, and the curing time is 5 to 20 min.

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