Application of nucleoside-modified graphene oxide in chiral compound recognition

Abstract

This application discloses the application of nucleoside-modified graphene oxide in the recognition of chiral compounds. Using graphene oxide as a raw material, this application modifies its surface with D- and L-configured deoxynucleosides through multiple steps to prepare chiral graphene oxide, and then applies it to chiral recognition and separation.

Description

Technical Field

[0001] This application belongs to the fields of organic chemistry and bioengineering. Specifically, this application provides the application of nucleoside-modified graphene oxide in the recognition of chiral compounds. Background Technology

[0002] Graphene oxide is a type of two-dimensional carbon material with various functional groups, and it has great application potential in energy storage, materials design, environmental science, and life sciences. To broaden the application scenarios of graphene oxide, researchers need to perform certain physical or chemical modifications to endow it with specific physical, chemical, or biological properties; this type of physical or chemical modification is also known as modification. Chemical modification of graphene oxide often utilizes functional groups such as carboxyl, hydroxyl, carbonyl, and epoxy ethyl groups in its structure as reaction sites, reacting them with molecules or functional groups containing optical, electrical, magnetic, or mechanical physical properties, specific chemical properties, or specific biological properties to achieve the functionalization of graphene oxide.

[0003] The identification and resolution of chiral compounds is a fundamental problem in medicinal chemistry, consumer chemistry, optical materials and life sciences. Developing materials with high specificity for chiral recognition and chiral enrichment has important theoretical significance and market value for new drugs and new materials. Summary of the Invention

[0004] This application creatively utilizes mirror-isomers of D- and L-configurations of deoxyribonucleotides as chiral recognition units, covalently loading them onto graphene oxide to prepare a class of chiral composite graphene materials with high chemical stability. This graphene oxide composite material exhibits the ability to recognize and enrich chiral compounds, demonstrating good selectivity in the enrichment of amino acid and amino alcohol samples.

[0005] We prepared functional graphene oxides with different chiralities by attaching D- and L-configurations of deoxynucleosides to graphene oxide. Through nucleophilic substitution reactions, we linked the epoxy groups in graphene oxide to the 3' or 5' hydroxyl groups of deoxynucleosides via ether bonds under the catalysis of an organic base, achieving covalent loading of D- or L-configurations of deoxynucleosides with graphene oxide, thus preparing composite graphene oxides containing different configurations and bases.

[0006] On the one hand, this application provides the application of nucleoside-modified graphene oxide in the recognition of chiral compounds.

[0007] Furthermore, the nucleoside is D-deoxynucleoside and / or L-deoxynucleoside.

[0008] Furthermore, the bases in the deoxynucleoside are selected from one or more of adenine, guanine, cytosine, and thymine.

[0009] The preferred amino groups are adenine, guanine, and cytosine, and the 3' or 5' hydroxyl groups of deoxynucleosides are unprotected or unmodified.

[0010] The graphene oxide can be prepared by the following method or a similar method, or by purchasing commercially available products: 100 grams of expanded graphite is dispersed in 20 kg of deionized water and added to a high-shear reactor. The reactor is evacuated to 120 Pa, and dispersed by high-shear grinding under vacuum at a speed of 2400 rpm for 20 minutes. Subsequently, the suspension is transferred to a high-pressure homogenizer under negative pressure, and the reactor is cleaned three times with argon gas. Then, deep exfoliation is performed at a pressure of not less than 80 MPa for not less than 4 hours. The homogenized graphene is then transferred to an ultrasonic device under argon protection, with an ultrasonic power of 9000 watts, a temperature of 30-35 degrees Celsius, and an ultrasonic time of not less than 60 minutes. The material is then spray-dried with an inlet air temperature of 185 degrees Celsius, a feed flow rate of 140 ml / min, and a nozzle speed of not less than 35000 rpm.

[0011] Furthermore, the preparation process of the nucleoside-modified graphene oxide includes:

[0012] Disperse 500 mg of graphene oxide with an oxygen content of not less than 0.75% in 5-40 mL of organic solvent and stir at room temperature for 0.5-3 hours. Add 20-80 mg of D- or L-configured deoxynucleoside and continue stirring for 1 hour. Then add 5-200 mg of organic base, sonicate for 1-3 hours, and continue stirring under nitrogen protection for 12-48 hours. After the reaction is complete, pour the reaction solution into 50-400 mL of deionized water. Dialyze the mixture in 1000-3000 mL of deionized water to remove the organic solvent and excess reactants. Dialyze 3-8 times until the pH is less than 8.5. Freeze-dry the dialysate.

[0013] Furthermore, the preparation process of the nucleoside-modified graphene oxide includes:

[0014] 500 mg of graphene oxide with an oxygen content of not less than 0.75% was dispersed in 20 mL of organic solvent and stirred at room temperature for 1 hour. Then, 50 mg of D- or L-deoxynucleoside was added, and stirring continued for another hour. Finally, 100 mg of organic base was added, and the mixture was sonicated for 2 hours. Stirring continued for 24 hours under nitrogen protection. After the reaction was complete, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove the organic solvent and excess reactants. Dialysis was performed 5 times until the pH was less than 7.55. The dialysate was then lyophilized.

[0015] Further,

[0016] The organic base is selected from, but not limited to, triethylamine, diisopropylethylamine, tributylamine, trioctylamine, pyridine, 2-methylpyridine, 3-methylpyridine, N,N-dimethylaminopyridine, 2,6-dimethylpyridine, N-methylmorpholine, N-methylpiperidine, 2-methylnaphthidine, 1,8-diazabicycloundec-7-ene or 1,5-diazabicyclo[4.3.0]-5-nonene;

[0017] The organic solvent is selected from, but not limited to, one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone, hexamethylphosphonic triamine, diethylene glycol dimethyl ether, and diethylene glycol dimethyl ether mixed in a certain proportion.

[0018] Furthermore, the preparation process of the nucleoside-modified graphene oxide includes:

[0019] Graphene oxide loaded with D-configuration deoxyadenosine:

[0020] 500 mg of graphene oxide with an oxygen content of not less than 0.75% was dispersed in 20 mL of dimethyl sulfoxide and stirred at room temperature for 1 hour. Then, 50 mg of D-configuration deoxyadenosine was added, and stirring continued for another hour. Finally, 100 mg of 1,8-diazabicycloundec-7-ene was added, and the mixture was sonicated for 2 hours. Stirring continued for 24 hours under nitrogen protection. After the reaction was complete, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. Dialysis was repeated 5 times until the pH was less than 7.5. The dialysate was lyophilized to obtain graphene oxide loaded with D-configuration deoxyadenosine.

[0021] Graphene oxide loaded with L-configuration deoxyadenosine:

[0022] 500 mg of graphene oxide with an oxygen content of not less than 0.75% was dispersed in 20 mL of dimethyl sulfoxide and stirred at room temperature for 1 hour. Then, 50 mg of L-deoxyadenosine was added, and stirring continued for another hour. Finally, 100 mg of N,N-dimethylaminopyridine was added, and the mixture was sonicated for 2 hours. Stirring continued for 24 hours under nitrogen protection. After the reaction was complete, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. Dialysis was repeated 5 times until the pH was less than 7.5. The dialysate was lyophilized to obtain graphene oxide loaded with L-deoxyadenosine.

[0023] Graphene oxide loaded with D-configuration deoxycytidine:

[0024] 500 mg of graphene oxide with an oxygen content of not less than 0.75% was dispersed in 20 mL of N-methylpyrrolidone and stirred at room temperature for 1 hour. Then, 50 mg of D-configuration deoxycytidine was added, and stirring continued for another hour. Finally, 100 mg of 2,6-dimethylpyridine was added, and the mixture was sonicated for 2 hours. Stirring continued for 24 hours under nitrogen protection. After the reaction was complete, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. Dialysis was repeated 5 times until the pH was less than 7.5. The dialysate was lyophilized to obtain graphene oxide loaded with D-configuration deoxycytidine.

[0025] Graphene oxide loaded with L-configuration deoxyguanosine:

[0026] 500 mg of graphene oxide with an oxygen content of not less than 0.75% was dispersed in 20 mL of diethylene glycol dimethyl ether and stirred at room temperature for 1 hour. Then, 50 mg of L-deoxyguanosine was added, and stirring continued for another hour. Finally, 100 mg of tributylamine was added, and the mixture was sonicated for 2 hours. Stirring continued for 24 hours under nitrogen protection. After the reaction was complete, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. Dialysis was repeated 5 times until the pH was less than 7.5. The dialysate was then lyophilized to obtain graphene oxide loaded with L-deoxyguanosine.

[0027] Furthermore, the identification is to detect chiral compounds or to prepare chiral compounds by resolution.

[0028] Furthermore, the chiral compound is selected from natural amino acids, non-natural amino acids, natural amino alcohols, and non-natural α-amino alcohols.

[0029] Furthermore, the chiral compound is phenylalanine or phenylethanolamine.

[0030] Non-limiting examples of chiral compounds include: native amino acids of D- or L-configuration, such as glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, and histidine; non-native α-amino acids of D- or L-configuration; native amino alcohols of D- or L-configuration obtained by reduction of native amino acids of D- or L-configuration; and α-amino alcohols of D- or L-configuration obtained by reduction of non-native α-amino acids of D- or L-configuration.

[0031] On the other hand, this application provides a kit or reagent combination for identifying chiral compounds, which includes the above-mentioned nucleoside-modified graphene oxide. Attached Figure Description

[0032] Figure 1 The general formula for D- and L-configured deoxynucleosides;

[0033] Figure 2 This is a schematic diagram of the reaction between graphene oxide and D- and L-configured deoxynucleosides (taking D- and L-configured deoxyadenosine as an example);

[0034] Figure 3 Liquid chromatography retention times for D- and L-phenylalanine configurations (15.452 min for L-phenylalanine and 15.599 min for D-phenylalanine);

[0035] Figure 4 The liquid chromatography retention time of the supernatant after centrifugation of graphene oxide loaded with D-configuration deoxyadenosine and D- and L-phenylalanine (15.968 min is the retention time of D-phenylalanine);

[0036] Figure 5 The liquid chromatography retention times for D- and L-configurations of phenylethanolamine are given. (12.700 min is the retention time for L-phenylethanolamine, and 12.945 min is the retention time for D-phenylethanolamine).

[0037] Figure 6 The liquid chromatography retention time of the supernatant after centrifugation of graphene oxide loaded with L-deoxycytidine and D- and L-phenylethanolamine is 12.613 min (the retention time of L-phenylethanolamine).

[0038] Figure 7 The complex is loaded with D-deoxyadenosine and L-configuration phenylalanine for chiral recognition. The carboxyl and amino groups in L-configuration phenylalanine can form more stable hydrogen bonds with the adenine in D-configuration adenosine (indicated by bold dashed lines), and the benzene ring of L-configuration phenylalanine forms π-π stacking with graphene oxide, further stabilizing the complex.

[0039] Figure 8 The complex is loaded with D-deoxyadenosine and D-configuration phenylalanine for chiral recognition. The D-configuration phenylalanine has a poor spatial configuration that does not match the sugar ring configuration of deoxyribose, resulting in unstable hydrogen bonds (represented by thin dashed lines) between its carboxyl and amino groups and the adenine in the D-configuration adenosine. The L-configuration phenylalanine also exhibits weak π-π stacking between its benzene ring and graphene oxide, leading to insufficient stability of the complex.

[0040] Figure 9The complex is loaded with L-deoxycytidine and D-configuration phenylethanolamine for chiral recognition. The hydroxyl and amino groups of the D-configuration phenylethanolamine can form more stable hydrogen bonds with the cytosine in the L-configuration adenosine (indicated by bold dashed lines), and the benzene ring of the D-configuration phenylethanolamine forms π-π stacking with graphene oxide, further stabilizing the complex.

[0041] Figure 10 The complex is loaded with L-deoxycytidine and L-configured phenylethanolamine for chiral recognition. The L-configured phenylethanolamine exhibits poor hydrogen bond stability (represented by thin dashed lines) due to the mismatch between its spatial configuration and the sugar ring configuration of deoxyribose. This leads to a significant reduction in the π-π stacking stability of the benzene ring of L-configured phenylethanolamine and graphene oxide, further decreasing the overall stability of the complex. Detailed Implementation

[0042] The following embodiments are provided to better understand the present invention, but are not limited thereto. These embodiments are for illustrative purposes only and do not limit the scope of protection of the present invention in any way.

[0043] Example 1: Instruments and Methods

[0044] Elemental analyzer

[0045] The instrument model was Vario EL Cube, the measurement mode was "CHN mode", and the sample volume was 10 mg. The pressure settings were: helium 0.2 MPa, oxygen 0.2 MPa; the temperature settings were: furnace 1 950℃; furnace 2 500℃; furnace 3 0℃; and acetanilide was used as the standard. Three sets of samples were measured in parallel.

[0046] High performance liquid chromatography

[0047] The instrument was an Agilent 1260, the mobile phase was acetonitrile and ultrapure water, the elution time was 40 min, and the flow rate was 1 mL / min. -1 The column temperature was 30℃, and the purification and separation column was a C18 column (4.6×250mm) with a concentration of 50 μmol·L⁻¹. -1 The injection volume was 20 μL.

[0048] Example 2 illustrates the linking of deoxyribonucleotides of different chiralities with graphene oxide.

[0049] Preparation of graphene oxide:

[0050] 100 grams of expanded graphite were dispersed in 20 kilograms of deionized water and added to a high-shear reactor. The reactor was evacuated to 120 Pa, and the graphite was dispersed under vacuum by high-shear grinding at 2400 rpm for 20 minutes. Subsequently, the suspension was transferred to a high-pressure homogenizer under negative pressure, and the reactor was cleaned three times with argon gas. Then, deep exfoliation was performed at an operating pressure of not less than 80 MPa for not less than 4 hours.

[0051] Homogenized graphene was transferred into an ultrasonic device under argon protection. The ultrasonic power was set to 9000 watts, the temperature to 30-35 degrees Celsius, and the ultrasonic time to be no less than 60 minutes. The material was then spray-dried with an inlet air temperature of 185 degrees Celsius, a feed flow rate of 140 ml / min, and a nozzle rotation speed of no less than 35000 rpm. The oxygen content of the product was determined by elemental analysis.

[0052] General synthesis steps:

[0053] 500 mg of graphene oxide (oxygen content not less than 0.75%) was dispersed in 20 mL of organic solvent and stirred at room temperature for 1 hour. Then, 50 mg of D- or L-deoxynucleoside was added, and stirring continued for another hour. Finally, 100 mg of an organic base was added, and the mixture was sonicated for 2 hours. Stirring continued for 24 hours under nitrogen protection. After the reaction was complete, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove the organic solvent and excess reactants. Dialysis was repeated 5 times until the pH was less than 7.5. The dialysate was then lyophilized to obtain graphene oxide loaded with D- or L-deoxynucleoside.

[0054] Specifically:

[0055] Graphene oxide loaded with D-configuration deoxyadenosine (D-dA):

[0056] 500 mg of graphene oxide (oxygen content not less than 0.75%) was dispersed in 20 mL of dimethyl sulfoxide and stirred at room temperature for 1 hour. Then, 50 mg of D-configuration deoxyadenosine was added, and stirring continued for another hour. Finally, 100 mg of 1,8-diazabicycloundec-7-ene was added, and the mixture was sonicated for 2 hours. Stirring continued for 24 hours under nitrogen protection. After the reaction was complete, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. Dialysis was repeated 5 times until the pH was less than 7.5. The dialysate was lyophilized to obtain graphene oxide loaded with D-configuration deoxyadenosine. The loading was 4.70 ± 0.05 μmol / g.

[0057] Graphene oxide loaded with L-configuration deoxyadenosine (L-dA):

[0058] 500 mg of graphene oxide (oxygen content not less than 0.75%) was dispersed in 20 mL of dimethyl sulfoxide and stirred at room temperature for 1 hour. 50 mg of L-deoxyadenosine was added, and stirring continued for another hour. Then, 100 mg of N,N-dimethylaminopyridine was added, and the mixture was sonicated for 2 hours. Stirring continued for 24 hours under nitrogen protection. After the reaction was complete, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. Dialysis was performed 5 times until the pH was less than 7.5. The dialysate was lyophilized to obtain graphene oxide loaded with L-deoxyadenosine. The loading was 4.65 ± 0.05 μmol / g.

[0059] Graphene oxide loaded with D-configuration deoxycytidine (D-dC):

[0060] 500 mg of graphene oxide (oxygen content not less than 0.75%) was dispersed in 20 mL of N-methylpyrrolidone and stirred at room temperature for 1 hour. Then, 50 mg of L-deoxycytidine was added, and stirring continued for another hour. Finally, 100 mg of 2,6-dimethylpyridine was added, and the mixture was sonicated for 2 hours. Stirring continued for 24 hours under nitrogen protection. After the reaction was complete, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. Dialysis was repeated 5 times until the pH was less than 7.5. Lyophilization of the dialysate yielded graphene oxide loaded with D-deoxycytidine. The loading was 5.53 ± 0.04 μmol / g.

[0061] Graphene oxide loaded with L-configuration deoxycytidine (L-dC):

[0062] 500 mg of graphene oxide (oxygen content not less than 0.75%) was dispersed in 20 mL of N-methylpyrrolidone and stirred at room temperature for 1 hour. Then, 50 mg of L-deoxycytidine was added, and stirring continued for another hour. Finally, 100 mg of N-methylmorpholine was added, and the mixture was sonicated for 2 hours. Stirring continued for 24 hours under nitrogen protection. After the reaction was complete, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. Dialysis was repeated 5 times until the pH was less than 7.5. Lyophilization of the dialysate yielded graphene oxide loaded with D-deoxycytidine. The loading was 5.54 ± 0.03 μmol / g.

[0063] Graphene oxide loaded with D-configuration deoxyguanosine (D-dG):

[0064] 500 mg of graphene oxide (oxygen content not less than 0.75%) was dispersed in 20 mL of diethylene glycol dimethyl ether and stirred at room temperature for 1 hour. Then, 50 mg of D-configuration deoxyguanosine was added, and stirring continued for another hour. Finally, 100 mg of tributylamine was added, and the mixture was sonicated for 2 hours. Stirring continued for 24 hours under nitrogen protection. After the reaction was complete, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. Dialysis was repeated 5 times until the pH was less than 7.5. Lyophilization of the dialysate yielded graphene oxide loaded with D-configuration deoxyguanosine, with a loading of 3.94 ± 0.07 μmol / g.

[0065] Graphene oxide loaded with L-configuration deoxyguanosine (L-dG):

[0066] 500 mg of graphene oxide (oxygen content not less than 0.75%) was dispersed in 20 mL of diethylene glycol dimethyl ether and stirred at room temperature for 1 hour. Then, 50 mg of L-deoxyguanosine was added, and stirring continued for another hour. Finally, 100 mg of diisopropylethylamine was added, and the mixture was sonicated for 2 hours. Stirring continued for 24 hours under nitrogen protection. After the reaction was complete, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. Dialysis was repeated 5 times until the pH was less than 7.5. Lyophilization of the dialysate yielded graphene oxide loaded with L-deoxyguanosine, with a loading of 3.96 ± 0.06 μmol / g.

[0067] Graphene oxide loaded with D-configuration deoxythymidine (D-dT):

[0068] 500 mg of graphene oxide (oxygen content not less than 0.75%) was dispersed in 20 mL of N-methylpyrrolidone and stirred at room temperature for 1 hour. Then, 50 mg of D-configuration deoxythymidine was added, and stirring continued for another hour. Finally, 100 mg of N-methylpiperidine was added, and the mixture was sonicated for 2 hours. Stirring continued for 24 hours under nitrogen protection. After the reaction was complete, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. Dialysis was repeated 5 times until the pH was less than 7.5. Lyophilization of the dialysate yielded graphene oxide loaded with D-configuration deoxythymidine. The loading was 6.15 ± 0.04 μmol / g.

[0069] Graphene oxide loaded with L-configuration deoxythymidine (L-dT):

[0070] 500 mg of graphene oxide (oxygen content not less than 0.75%) was dispersed in 20 mL of N-methylpyrrolidone and stirred at room temperature for 1 hour. Then, 50 mg of L-deoxythymidine was added, and stirring continued for another hour. Finally, 100 mg of pyridine was added, and the mixture was sonicated for 2 hours. Stirring continued for 24 hours under nitrogen protection. After the reaction was complete, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. Dialysis was repeated 5 times until the pH was less than 7.5. Lyophilization of the dialysate yielded graphene oxide loaded with L-deoxythymidine. The loading was 6.13 ± 0.03 μmol / g.

[0071] The loading of deoxynucleosides on graphene oxide was determined by elemental analysis. Since graphene oxide does not contain nitrogen (N), the loading of deoxynucleosides could be estimated by measuring the change in the ratio of N to C.

[0072] Table 1. Amount of D- and L-configured deoxyribonucleotides loaded on graphene oxide

[0073]

[0074]

[0075] By investigating the types of organic bases, reaction solvents, reaction temperatures, and reaction times, the efficiency of loading graphene oxide with different configurations of deoxyribonucleosides was determined, and the expected functionalized graphene oxide was obtained. Furthermore, the graphene oxide loaded with different configurations of deoxyribonucleosides exhibits specific selective recognition ability for amino acids and amino alcohols of different chiralities.

[0076] In this type of composite graphene material, the chirality of the deoxypentose ring endows the nitrogen-containing base with chiral recognition ability, enabling highly selective recognition and separation of small molecules or compounds that can form hydrogen bonds, such as D- or L-configured amino acids or amino alcohols, which can be used for the selective enrichment of chiral molecules.

[0077] (In this application, we do not consider the issue of increasing the loading by optimizing the reaction system. In the table above, the difference in loading is due to the difference in the base structure of the nucleosides.)

[0078] Example 3: Recognition of chiral molecules by graphene oxide loaded with different chiral deoxyribonucleotides

[0079] 100 mg of graphene oxide loaded with deoxynucleosides was dispersed in 10 mL of deionized water. 1 mL of 0.5 mM equimolar mixture of D- and L-configurations of chiral molecules was added. The mixture was sealed in a dark place and allowed to stand overnight at room temperature. The graphene oxide was removed by centrifugation, and the supernatant was filtered through a 0.22 μm aqueous membrane and analyzed by liquid chromatography.

[0080] For the principle of chiral recognition with phenylalanine and phenylethanolamine, see [link to relevant documentation]. Figure 7-10 .

[0081] Specific Implementation Case Study 1

[0082] 100 mg of graphene oxide loaded with D-configuration deoxyadenosine (i.e., D-configuration dA) was dispersed in 10 mL of deionized water. 1 mL of an equimolar mixture of D- and L-configurations of phenylalanine (0.5 mM total concentration) was added, ensuring both D- and L-configurations were at a concentration of 0.25 mM. The mixture was then sealed in a light-protected container and allowed to stand overnight at room temperature. The graphene oxide was removed by centrifugation, and the supernatant was filtered through a 0.22 μm aqueous membrane and analyzed by liquid chromatography.

[0083] like Figure 3 As shown, the retention time of L-phenylalanine was 15.452 minutes, and the retention time of D-phenylalanine was 15.599 minutes; Figure 4 As shown, after graphene oxide loaded with D-configuration deoxyadenosine was mixed with D- and L-phenylalanine, the retention time of D-phenylalanine in the supernatant after centrifugation was 15.968 minutes.

[0084] Specific Implementation Case 2

[0085] 100 mg of graphene oxide loaded with D-configuration deoxyadenosine (i.e., D-configuration dC) was dispersed in 10 mL of deionized water. 1 mL of an equimolar mixture of D- and L-configurations of phenylethanolamine (0.5 mM total concentration, i.e., both D- and L-configurations of phenylethanolamine at 0.25 mM) was added and the mixture was sealed and kept in a dark place at room temperature overnight. The graphene oxide was removed by centrifugation, and the supernatant was filtered through a 0.22 μm aqueous membrane and analyzed by liquid chromatography.

[0086] like Figure 5 As shown, the retention time of L-phenylethanolamine was 12.700 minutes, and the retention time of D-phenylethanolamine was 12.945 minutes; Figure 6 As shown, after graphene oxide loaded with L-configuration deoxycytidine was mixed with D- and L-phenylethanolamine, the retention time of L-phenylethanolamine in the supernatant after centrifugation was 12.613 minutes.

[0087] We used high-performance liquid chromatography (HPLC) to investigate the efficiency of chiral recognition by modified graphene. We observed HPLC retention times of 15.955 min for D- and 15.452 min for L-phenylalanine. When D- and L-phenylalanine were mixed with graphene oxide loaded with D-deoxyadenosine, the supernatant after centrifugation contained only D-phenylalanine, with an HPLC retention time of 15.968 min. This result confirms that L-phenylalanine was completely adsorbed by graphene oxide loaded with D-deoxyadenosine.

[0088] The liquid chromatography retention times of D- and L-configured phenylethanolamine were 12.945 min and 12.700 min, respectively. When graphene oxide loaded with L-configured deoxycytidine was mixed with D- and L-phenylethanolamine, the supernatant after centrifugation contained only L-phenylethanolamine, with a liquid chromatography retention time of 12.613 min, proving that D-configured phenylethanolamine was completely adsorbed by graphene oxide loaded with L-configured deoxycytidine.

[0089] The above experimental results demonstrate that graphene oxide loaded with deoxyribonucleosides of different configurations can adsorb α-amino acids or α-amino alcohols of different configurations.

Claims

1. The application of nucleoside-modified graphene oxide in the recognition of chiral compounds, characterized in that, The nucleoside is a D-deoxynucleoside and / or an L-deoxynucleoside; the bases in the D-deoxynucleoside and / or L-deoxynucleoside are selected from one or more of adenine, guanine, cytosine, and thymine. The preparation process of the nucleoside-modified graphene oxide includes: Disperse 500 mg of graphene oxide with an oxygen content of not less than 0.75% in 5-40 mL of organic solvent and stir at room temperature for 0.5-3 hours. Add 20-80 mg of D-deoxynucleoside or L-deoxynucleoside and continue stirring for 1 hour. Then add 5-200 mg of organic base and sonicate for 1-3 hours. Continue stirring under nitrogen protection for 12-48 hours. After the reaction is complete, pour the reaction solution into 50-400 mL of deionized water. Dialyze the mixture in 1000-3000 mL of deionized water to remove the organic solvent and excess reactants. Dialyze 3-8 times until the pH is less than 8.

5. Freeze-dry the dialysate.

2. The application according to claim 1, wherein the preparation process of the nucleoside-modified graphene oxide includes: 500 mg of graphene oxide with an oxygen content of not less than 0.75% was dispersed in 20 mL of organic solvent and stirred at room temperature for 1 hour. 50 mg of D-deoxynucleoside or L-deoxynucleoside was added, and stirring was continued for 1 hour. Then, 100 mg of organic base was added, and the mixture was sonicated for 2 hours. Stirring was continued for 24 hours under nitrogen protection. After the reaction was completed, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove the organic solvent and excess reactants. The dialysate was dialyzed 5 times until the pH was less than 7.

55. The dialysate was then lyophilized.

3. The application according to claim 2, wherein the organic base in the preparation of the nucleoside-modified graphene oxide is selected from triethylamine, diisopropylethylamine, tributylamine, trioctylamine, pyridine, 2-methylpyridine, 3-methylpyridine, N,N-dimethylaminopyridine, 2,6-dimethylpyridine, N-methylmorpholine, N-methylpiperidine, 2-methylnaphthidine, 1,8-diazabicycloundec-7-ene or 1,5-diazabicyclo[4.3.0]-5-nonene; The organic solvent is selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone, hexamethylphosphonic triamine, diethylene glycol dimethyl ether, and diethylene glycol dimethyl ether.

4. The application according to claim 3, wherein the preparation process of the nucleoside-modified graphene oxide is as follows: Graphene oxide loaded with D-configuration deoxyadenosine: 500 mg of graphene oxide with an oxygen content of not less than 0.75% was dispersed in 20 mL of dimethyl sulfoxide and stirred at room temperature for 1 hour. 50 mg of D-configuration deoxyadenosine was added, and stirring was continued for 1 hour. Then, 100 mg of 1,8-diazabicycloundec-7-ene was added, and the mixture was sonicated for 2 hours. Stirring was continued for 24 hours under nitrogen protection. After the reaction was completed, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. The dialysate was dialyzed 5 times until the pH was less than 7.

5. The dialysate was lyophilized to obtain graphene oxide loaded with D-configuration deoxyadenosine. And / or, Graphene oxide loaded with L-configuration deoxyadenosine: 500 mg of graphene oxide with an oxygen content of not less than 0.75% was dispersed in 20 mL of dimethyl sulfoxide and stirred at room temperature for 1 hour. 50 mg of L-deoxyadenosine was added, and stirring was continued for 1 hour. Then, 100 mg of N,N-dimethylaminopyridine was added, and the mixture was sonicated for 2 hours. Stirring was continued for 24 hours under nitrogen protection. After the reaction was completed, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. The dialysate was dialyzed 5 times until the pH was less than 7.

5. The dialysate was lyophilized to obtain graphene oxide loaded with L-deoxyadenosine. And / or, Graphene oxide loaded with D-configuration deoxycytidine: 500 mg of graphene oxide with an oxygen content of not less than 0.75% was dispersed in 20 mL of N-methylpyrrolidone and stirred at room temperature for 1 hour. 50 mg of D-configuration deoxycytidine was added, and stirring was continued for another hour. Then, 100 mg of 2,6-dimethylpyridine was added, and the mixture was sonicated for 2 hours. Stirring was continued for 24 hours under nitrogen protection. After the reaction was completed, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. The dialysate was dialyzed 5 times until the pH was less than 7.

5. The dialysate was lyophilized to obtain graphene oxide loaded with D-configuration deoxycytidine. And / or, Graphene oxide loaded with L-configuration deoxyguanosine: 500 mg of graphene oxide with an oxygen content of not less than 0.75% was dispersed in 20 mL of diethylene glycol dimethyl ether and stirred at room temperature for 1 hour. 50 mg of L-configuration deoxyguanosine was added, and stirring was continued for another hour. Then, 100 mg of tributylamine was added, and the mixture was sonicated for 2 hours. Stirring was continued for 24 hours under nitrogen protection. After the reaction was completed, the reaction solution was poured into 100 mL of deionized water. The mixture was then dialyzed in 2000 mL of deionized water to remove organic solvents and excess reactants. The dialysate was dialyzed 5 times until the pH was less than 7.

5. The dialysate was lyophilized to obtain graphene oxide loaded with L-configuration deoxyguanosine.

5. The application according to any one of claims 1-4, wherein the identification is the detection of a chiral compound or the resolution preparation of a chiral compound.

6. The application according to claim 5, wherein the chiral compound is selected from natural amino acids, non-natural amino acids, natural amino alcohols, and non-natural α-amino alcohols.

7. The application according to claim 6, wherein the chiral compound is phenylalanine or phenylethanolamine.

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