A method for preparing dehydroabscisic acid locust bean gum bonded silica microspheres

Abstract

This invention discloses a method for preparing dehydroabscisic acid locust bean gum ester-bonded silica microspheres. The method uses dehydroabscisic acid locust bean gum ester (DLE) as a functional monomer. By adjusting the degree of substitution of DLE (0.001–2.5), an esterification reaction is carried out with a silica derivative to obtain dehydroabscisic acid locust bean gum ester-bonded silica microspheres (DLE@SiO231). These microspheres are then treated with a blocking agent to obtain blocked microspheres (DLE@SiO231M). The resulting microspheres have a particle size of 2–10 μm, an average pore size of 2–70 nm, and a specific surface area of ​​50–600 m². 2 The material exhibits uniform particle size and high mechanical strength. It can be used as a packing material for high-performance liquid chromatography (HPLC) columns or for solid-phase extraction. Due to the introduction of DLE (dihydrolamine), it possesses amphiphilic properties and demonstrates excellent selective separation capabilities for saponin drugs, showing broad application prospects in the field of drug separation and purification.

Description

Technical Field

[0001] This invention belongs to the field of high-performance liquid chromatography. Specifically, this invention relates to a method for preparing dehydroabscisic acid locust bean gum-bonded silica microspheres. Background Technology

[0002] Locust bean gum, a natural polysaccharide extracted from the endosperm of locust tree seeds, is mainly composed of galactose and mannose residues. It is commonly used in the food industry as a thickener, stabilizer, and gelling agent. Its molecular chain is rich in hydroxyl groups, which not only endow it with good hydrophilicity and hydration ability, but also, due to its excellent water solubility, environmental friendliness, and economic efficiency, make locust bean gum and its derivatives important functional materials in multiple industrial fields.

[0003] Dehydroabietic acid, derived from natural rosin, is a resin acid with a unique tricyclic phenanthrene skeleton and carboxyl groups. As a renewable resource, it possesses good biocompatibility and low toxicity, and its derivatives have been applied in the fields of surfactants, chiral resolving agents, and functional material preparation. Research has confirmed that the hydrophobic skeleton of dehydroabietic acid can be used to bond it to the surface of modified silica, thereby preparing hydrophobic silica microspheres.

[0004] Based on the advantages of the two natural raw materials mentioned above, this invention develops an amphiphilic microsphere using dehydroabscisic acid locust bean gum ester (DLE) bonded to silica as the core. By controlling the degree of substitution of dehydroabscisic acid locust bean gum ester (0.001–2.5), the hydrophilic / hydrophobic properties of the microspheres can be precisely adjusted, giving the microspheres a controllable hydrophobic / hydrophilic balance. This microsphere not only has high mechanical strength and a relatively simple preparation process, but also possesses both hydrophilic and hydrophobic properties. When used as a stationary phase packing material, it can efficiently and rapidly separate hydrophobic and hydrophilic substances; especially in the separation of saponin drugs, it exhibits excellent selective separation ability. Furthermore, the chromatographic column prepared based on this microsphere has excellent flowability, which makes it show broad application prospects in the field of drug separation and purification. Summary of the Invention

[0005] The core objective of this invention is to provide a method for preparing dehydroabscisic acid locust bean gum ester (DLE) bonded silica microspheres. This method not only provides practical technical guidance for the synthesis of polysaccharide esters with silica, but also reduces the amount of organic solvents used in the preparation process, effectively lowering material costs and environmental burden. Simultaneously, modern analytical techniques such as infrared spectroscopy, thermogravimetric analysis, specific surface area and pore size analysis, and scanning electron microscopy can be used to systematically characterize key performance indicators of the prepared microspheres, including DLE bonding amount, specific surface area, pore structure parameters, surface micromorphology, and surface chemical functional group composition, ensuring controllable product quality.

[0006] This invention also relates to modified dehydroabscisic acid locust bean gum ester bonded silica microspheres. These microspheres are prepared using modified silica as a matrix by covalently bonding dehydroabscisic acid locust bean gum ester (DLE) to the surface of the modified silica. Due to their unique amphiphilic structure and stable physicochemical properties, these microspheres can be widely used as stationary phase packing materials and solid-phase extraction materials in high-performance liquid chromatography (HPLC). Their specific chemical structural formula is shown below:

[0007]

[0008] Furthermore, the silica has a particle size of 2–10 μm, an average pore size range of 2–70 nm, and a specific surface area of ​​50–600 m² / g.

[0009] This invention also provides a method for preparing dehydroabscisic acid locust bean gum-bonded silica microspheres, comprising the following steps:

[0010] a. Activation of silica: Add silica to a 1-30% HCl solution at a mass-to-volume ratio of 1:5-50, and stir the reaction at 60-100℃ for 8-16 hours. After the reaction is complete, filter the solution, wash the filter cake several times with deionized water until neutral, and finally dry it in a vacuum drying oven for 12 hours. Name it SiO2-OH.

[0011] b. Aminated silica: The activated silica was added to toluene at a mass-to-volume ratio of 1:10-40, followed by 1-30 volumes of 3-aminopropyltrimethoxysilane. The mixture was stirred at 60-100°C for 8-16 hours under an inert gas atmosphere. After the reaction was complete, the mixture was washed several times with solvent and finally dried in a vacuum oven for 12 hours. It was named SiO2-NH2.

[0012] c. Carboxylated silica: The above-mentioned aminated silica was added to toluene at a mass-to-volume ratio of 1:10–40, followed by succinic anhydride at a mass-to-volume ratio of 1:0.1–4 and triethylamine at a mass-to-volume ratio of 1:0.1–4. The mixture was stirred and reacted at 30–100°C for 2–12 h under an inert gas atmosphere. After the reaction was completed, the mixture was washed several times with solvent and finally dried in a vacuum drying oven for 12 h. It was named SiO2-COOH.

[0013] d. Acyl-Chalinated Silica: The above-mentioned carboxylated silica was added to toluene at a mass-to-volume ratio of 1:10–40, followed by the addition of oxaloyl chloride at a mass-to-volume ratio of 1:0.5–10. The reaction was carried out at 20–50 °C for 2–10 h, and then at 50–100 °C for 1–4 h. After the reaction was completed, the sample was washed several times with solvent and finally dried in a vacuum drying oven for 12 h. It was named SiO2-COCl.

[0014] e. Dehydroabscisic acid locust bean gum bonded to silica: The above-mentioned acyl chloride silica was added to pyridine at a mass-to-volume ratio of 1:10-40. Subsequently, dehydroabscisic acid locust bean gum with a certain degree of substitution was added, with a mass ratio of 1:0.1-20 to the acyl chloride silica. The reaction was carried out under an inert gas atmosphere at 40-120°C with stirring for 4-24 hours. After the reaction was completed, a blocking agent was added to the system and the reaction was continued for 1 hour. After the reaction was completed, the system was washed several times with solvent and finally dried in a vacuum drying oven for 12 hours. It was named DLE@SiO231M.

[0015] Furthermore, the degree of substitution of the dehydroabscitic acid locust bean gum ester is 0.001 to 2.5.

[0016] Furthermore, the inert gas is nitrogen or argon.

[0017] Furthermore, the preparation method includes a step of washing multiple times with a solvent, wherein the solvent is two or more of pyridine, methanol, acetone, or anhydrous diethyl ether.

[0018] Furthermore, the sealing agent is methanol, ethanol, propanol, or butanol, etc.

[0019] The technical principle of this invention is as follows: Figure 1 This paper presents the preparation route of dehydroabscisic acid locust bean gum-bonded silica microspheres (DLE@SiO231M). As shown in the figure, silica is first activated to bond its surface with the silane coupling agent 3-aminopropyltrimethoxysilane, thereby introducing amino groups to obtain aminated silica. Subsequently, the aminated silica reacts with succinic anhydride to achieve carboxyl functionalization. Next, the carboxyl groups are converted into acyl chloride groups under the action of oxaloyl chloride to prepare acyl chloride silica. Finally, dehydroabscisic acid locust bean gum is bonded to the surface of acyl chloride silica through an esterification reaction to obtain DLE@SiO231 microspheres. Then, a blocking agent is added to block the carboxyl groups to obtain DLE@SiO231M microspheres. The prepared microspheres are amphiphilic. In addition, the prepared stationary phase filler has good flowability.

[0020] Compared with the prior art, the present invention has the following technical advantages:

[0021] (1) The DLE@SiO231 and DLE@SiO231M microspheres prepared in this invention are amphiphilic. The microsphere structure contains both a phenanthrene hydrophobic framework and a hydroxyl hydrophilic group, giving it both hydrophobicity and hydrophilicity, and exhibiting good steric selectivity.

[0022] (2) The preparation methods of DLE@SiO231 and DLE@SiO231M microspheres are simple to operate, requiring no complex equipment or high costs, which is conducive to large-scale production. As a stationary phase packing material, these microspheres have good flowability and excellent separation selectivity for saponin drugs, providing a new technical solution for the separation and purification of complex drug systems. Attached Figure Description Figure 1 This is a schematic diagram of the preparation route of DLE@SiO231 and DLE@SiO231M of the present invention. Figure 2 Infrared spectra of SiO2, SiO2-NH2, SiO2-COOH and 141DLE@SiO231 microspheres. Figure 3 Thermogravimetric diagrams of SiO2, SiO2-NH2, SiO2-COOH and 141DLE@SiO231 microspheres. Figure 4 Nitrogen adsorption-desorption curves (a) and pore size distribution diagram (b) for SiO2, SiO2-COOH and 141DLE@SiO231M microspheres. Figure 5 Scanning electron microscope (SEM) images of SiO2 (a), (b) and 141DLE@SiO231M (c), (d) microspheres. Figure 6 Acid value diagrams for SiO2-COOH, 141DLE@SiO231, and 141DLE@SiO231M. Figure 7 Flowability test chromatograms for 141DLE@SiO231 and 141DLE@SiO231M columns. Figure 8 Tanaka HILIC chromatograms of 141DLE@SiO231 and 141DLE@SiO231M columns. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will now be described in further detail with reference to specific embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of protection of this invention.

[0024] Preparation Example 1

[0025] A method for preparing dehydroabscisic acid locust bean gum bonded silica microspheres includes the following steps:

[0026] a. Activation of silica: Add 5.0 g of silica to 70 mL of 10% HCl solution and stir at 80 °C for 12 h. After the reaction is complete, filter, wash the filter cake several times with deionized water until neutral, and finally dry it in a vacuum drying oven for 12 h. Name it SiO2-OH.

[0027] b. Aminated silica: 1.0 g of the activated silica obtained above was added to 30 mL of toluene, followed by 5 mL of 3-aminopropyltrimethoxysilane. The mixture was stirred at 80 °C for 12 h under a N2 atmosphere. After the reaction was complete, the silica was washed several times with methanol and acetone, and finally dried in a vacuum drying oven for 12 h. It was named SiO2-NH2.

[0028] c. Carboxylated silica: Add 1.0 g of the above-mentioned aminated silica to 30 mL of toluene, then add 1.0 g of succinic anhydride and 1.0 mL of triethylamine. Stir the mixture at 40 °C for 5 h under a nitrogen atmosphere. After the reaction is complete, wash repeatedly with methanol and acetone, and finally dry in a vacuum drying oven for 12 h. Name it SiO2-COOH.

[0029] d. Acyl-Chalinated Silica: 0.1 g of the above-mentioned carboxylated silica was dispersed in 30 mL of toluene, and then 5 mL of oxalyl chloride was added. The reaction was carried out at 30 °C for 5 h, followed by a reaction at 70 °C for 4 h. After the reaction was completed, the sample was washed several times with diethyl ether and finally dried in a vacuum drying oven for 12 h. It was named SiO2-COCl.

[0030] e. Dehydroabscisic acid locust bean gum bonded to silica: 1.0 g of the above-mentioned acyl chloride silica was dispersed in 40 mL of pyridine, followed by the addition of 0.6 g of dehydroabscisic acid locust bean gum with a degree of substitution of 1.41. The reaction was carried out under N2 protection and stirred at 100 °C for 12 h. After the reaction was complete, the sample was washed repeatedly with pyridine and acetone, and finally dried in a vacuum drying oven for 12 h to obtain the sample, named 141DLE@SiO231.

[0031] Preparation Example 2

[0032] A method for preparing dehydroabscisic acid locust bean gum bonded silica microspheres includes the following steps:

[0033] a. Activation of silica: Add 5.0 g of silica to 70 mL of 10% HCl solution and stir at 80 °C for 12 h. After the reaction is complete, filter, wash the filter cake several times with deionized water until neutral, and finally dry it in a vacuum drying oven for 12 h. Name it SiO2-OH.

[0034] b. Aminated silica: 1.0 g of the activated silica obtained above was added to 30 mL of toluene, followed by 5 mL of 3-aminopropyltrimethoxysilane. The mixture was stirred at 80 °C for 12 h under a N2 atmosphere. After the reaction was complete, the silica was washed several times with methanol and acetone, and finally dried in a vacuum drying oven for 12 h. It was named SiO2-NH2.

[0035] c. Carboxylated silica: Add 1.0 g of the above-mentioned aminated silica to 30 mL of toluene, then add 1.0 g of succinic anhydride and 1.0 mL of triethylamine. Stir the mixture at 40 °C for 5 h under a nitrogen atmosphere. After the reaction is complete, wash repeatedly with methanol and acetone, and finally dry in a vacuum drying oven for 12 h. Name it SiO2-COOH.

[0036] d. Acyl-Chalinated Silica: 0.1 g of the above-mentioned carboxylated silica was dispersed in 30 mL of toluene, and then 5 mL of oxalyl chloride was added. The reaction was carried out at 30 °C for 5 h, followed by a reaction at 70 °C for 4 h. After the reaction was completed, the sample was washed several times with diethyl ether and finally dried in a vacuum drying oven for 12 h. It was named SiO2-COCl.

[0037] e. Dehydroabscisic acid locust bean gum bonded to silica: 1.0 g of the above-mentioned acyl chloride silica was dispersed in 40 mL of pyridine, followed by the addition of 0.6 g of dehydroabscisic acid locust bean gum with a degree of substitution of 1.41. The reaction was carried out under N2 protection and stirred at 100 °C for 12 h. After the reaction was complete, methanol was added to the system and the reaction continued for 1 h. The product was washed repeatedly with pyridine and acetone, and finally dried in a vacuum drying oven for 12 h to obtain the sample, named 141DLE@SiO231M.

[0038] Preparation Example 3

[0039] A method for preparing dehydroabscisic acid locust bean gum ester-bonded silica microspheres differs from Example 1 in that:

[0040] The degree of substitution of dehydroabscisic acid locust bean gum ester was 0.97. The obtained sample product was named 097DLE@SiO231.

[0041] Preparation Example 4

[0042] A method for preparing dehydroabscisic acid locust bean gum ester-bonded silica microspheres differs from Example 1 in that:

[0043] The degree of substitution of dehydroabscisic acid locust bean gum ester was 0.53. The obtained sample product was named 053DLE@SiO231.

[0044] Preparation Example 5

[0045] A method for preparing dehydroabscisic acid locust bean gum ester-bonded silica microspheres differs from Example 2 in that:

[0046] The degree of substitution of dehydroabscisic acid locust bean gum ester was 0.97. The obtained sample product was named 097DLE@SiO231M.

[0047] Preparation Example 6

[0048] A method for preparing dehydroabscisic acid locust bean gum ester-bonded silica microspheres differs from Example 2 in that:

[0049] The degree of substitution of dehydroabscisic acid locust bean gum ester was 0.53. The obtained sample product was named 053DLE@SiO231M.

[0050] The microspheres 141DLE@SiO231 and 141DLE@SiO231M were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, specific surface area and pore structure analysis, scanning electron microscopy, and acid value analysis. The results are as follows:

[0051] The SiO2, SiO2-NH2, SiO2-COOH, and 141DLE@SiO231 samples synthesized in Example 1 were characterized by infrared spectroscopy, and the results are as follows: Figure 2 As shown in the figure, the strong absorption peak at 1061 cm⁻¹ is attributed to the antisymmetric stretching vibration of the Si-O-Si framework; the characteristic peak at 1695 cm⁻¹ is the stretching vibration of the carbonyl group (C=O); the absorption peaks at 2898 cm⁻¹ and 2988 cm⁻¹ can be attributed to the stretching vibrations of -CH₃ and -CH₂, respectively; and the peak at 3668 cm⁻¹ is attributed to the stretching vibration of -OH. These characteristic peaks indicate that dehydroabscisic acid locust bean gum ester has been successfully bonded to the modified silica surface.

[0052] Thermogravimetric analysis was performed on SiO2, SiO2-NH2, SiO2-COOH, and 141DLE@SiO231 synthesized in Example 1. The results are as follows: Figure 3 As shown, the mass loss of SiO2 microspheres below 120℃ can be attributed to the volatilization of surface-adsorbed water. The total mass loss of 141DLE@SiO231 was 15.54%, indicating that dehydroabscisic acid locust bean gum ester has been successfully bonded to the surface of silica microspheres.

[0053] The SiO2, SiO2-COOH, and 141DLE@SiO231M synthesized in Example 2 were characterized by BET. The N2 adsorption-desorption isotherms of the SiO2, SiO2-COOH, and 141DLE@SiO231M microspheres are shown in Figure 4(a), along with their pore size distribution. Figure 4As shown in (b), the results indicate that the average pore size of the 141DLE@SiO231M microspheres is 9.02 nm, and the specific surface area reaches 266.65 m². 2 / g, possessing a high specific surface area and suitable pore size. From Figure 4 (a) It can be seen that the nitrogen adsorption-desorption curves exhibit typical type IV isotherm characteristics, accompanied by a significant hysteresis loop. This phenomenon indicates that the material has a uniform pore size distribution; combined with Figure 4 (b) Pore size distribution analysis showed that the most probable pore size of the microspheres fell within the mesoporous range of 2-50 nm, confirming that the modification process did not destroy the mesoporous structure of silica and that it still maintained its mesoporous properties. This indicates that the 141DLE@SiO231M microspheres still have a large specific surface area and pore size, meeting the requirements for their use as chromatographic materials.

[0054] The SiO2 and 141DLE@SiO231M samples prepared in Preparation Example 2 were characterized by scanning electron microscopy (SEM), and the results are as follows: Figure 5 As shown in the figure, both SiO2 and 141DLE@SiO231M exhibit good spherical morphology and relatively uniform particle size distribution. The microstructure and morphology of SiO2 and 141DLE@SiO231M remain basically consistent and have not undergone significant changes, indicating that the reaction process did not destroy the mesoporous structure of SiO2, and the materials still meet the basic requirements for use as chromatographic packing materials.

[0055] The acid values ​​of SiO2, SiO2-COOH, 141DLE@SiO231, and 141DLE@SiO231M prepared in Examples 1 and 2 were determined, and the results are as follows: Figure 6 As shown in the figure, the acid value decreases as the modified silica bonds with dehydroabscisic acid locust bean gum ester, and further decreases as the microspheres are encapsulated. This indicates that the dehydroabscisic acid locust bean gum ester is successfully bonded to the modified silica, and the encapsulating agent successfully encapsulates the microspheres.

[0056] The microspheres prepared in Examples 3 to 6 were subjected to the above tests, and the results were basically consistent with those above, further indicating that the dehydroabscisic acid locust bean gum bonded silica microspheres prepared in this invention have stable performance and good reproducibility.

[0057] Application Example 1

[0058] Packing of a dehydroabscisic acid locust bean gum bonded silica column

[0059] The modified silica microspheres were dispersed in chloroform and sonicated to ensure uniform dispersion. Then, a column packer was used to pack the microspheres at a constant pressure of 4000 psi for 50 minutes. After the column pressure reached equilibrium, the column was removed and plugged, thus obtaining a dehydroabscisic acid locust bean gum-bonded silica column.

[0060] Application Example 2

[0061] Flowability of dehydroabscisic acid locust bean gum bonded silica column

[0062] Using pure methanol and pure acetonitrile as mobile phases, the relationship between the flow rate and background pressure of 141DLE@SiO231 and 141DLE@SiO231M columns in the range of 0.1–1.2 mL / min was investigated. The results are as follows: Figure 7 As shown, the flow rate of the chromatographic column exhibits a good linear relationship with the background pressure, and the linear correlation coefficient R0 is [value missing]. 2 All values ​​are greater than 0.999, indicating that the column has good flow performance and meets the requirements for use of high performance liquid chromatography columns.

[0063] Application Example 3

[0064] Tanaka HILIC Standard Tests for Dehydroabscisic Acid Locust Bean Gum Bonded Silica Column

[0065] Reagents: uridine, 5-methyluridine, 2-deoxyuridine, vidarabine, adenosine, 3-deoxyguanosine, 2-deoxyguanosine, 4-nitrophenyl-α-D-glucopyranoside, 4-nitrophenyl-β-D-glucopyranoside, p-toluenesulfonic acid, phenyltrimethylammonium chloride, theobromine, theophylline.

[0066] Chromatographic conditions: ACN / 20mM NH4Ac (pH=4.7) (90 / 10, v / v); column temperature: 30℃; detection wavelength: 254nm; flow rate: 0.5mL / min; injection volume: 20μL. Columns: 141DLE@SiO231 and 141DLE@SiO231M. Toluene was used as a dead time marker.

[0067] The results are as follows Figure 8 As shown in the figure, the hydrophilicity of 141DLE@SiO231M is 0.44 higher than that of 141DLE@SiO231, proving that the carboxyl group blocking was successful and enhanced the hydrophilicity of the column. Regarding hydroxyl selectivity, blocking the carboxyl group exposes more hydroxyl groups, thus improving hydroxyl selectivity. Regarding the pH of the stationary phase surface, blocking the carboxyl group reduces the number of acidic groups on the stationary phase surface, causing the pH of the HILIC Tanaka stationary phase surface to tend to increase. This indicates that 141DLE@SiO231 and 141DLE@SiO231M are successfully bonded and have the potential to separate complex compounds.

[0068] It should be noted that when numerical ranges are involved in this invention, it should be understood that both endpoints of each numerical range and any value between the two endpoints can be selected. Since the steps and methods used are the same as in the embodiments, preferred embodiments are described here to avoid redundancy. Although preferred embodiments of the invention have been described, those skilled in the art, once they understand the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this invention.

[0069] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. Dehydroabietic acid guar gum ester-bonded silica microspheres, characterized by: The microspheres are prepared by dehydroabietic acid locust bean gum ester bonding on the surface of modified silica, and the structural formula is shown as follows.

2. The dehydroabietic acid locust bean gum ester-bonded silica microspheres according to claim 1, characterized by: The silica has a particle size of 2-10 μm, an average pore size of 2-70 nm, and a specific surface area of 50-600 m 2 / g.

3. A process for preparing dehydroabietic acid-locust bean gum ester-bonded silica microspheres according to claim 1, characterized by, The method comprises the following steps: a. Activated silica: the silica is added into 1-30% HCl solution at a mass-volume ratio of 1:5-50, and stirred and reacted at 60-100°C for 8-16h. After the reaction is completed, filtration is performed, the filter cake is washed with deionized water for multiple times until neutral, and finally dried in a vacuum drying box for 12h. Denoted as SiO2-OH. b. Aminated silica: the activated silica is added into toluene at a mass-volume ratio of 1:10-40, and then 3-aminopropyltrimethoxysilane is added at a volume ratio of 1-30, and stirred and reacted at 60-100°C for 8-16h under an inert gas atmosphere. After the reaction is completed, the product is washed with a solvent for multiple times, and finally dried in a vacuum drying box for 12h. Denoted as SiO2-NH2. c. Carboxylated silica: the aminated silica is added into toluene at a mass-volume ratio of 1:10-40, and then succinic anhydride is added at a mass ratio of 1:0.1-4, and triethylamine is added at a mass-volume ratio of 1:0.1-4, and stirred and reacted at 30-100°C for 2-12h under an inert gas atmosphere. After the reaction is completed, the product is washed with a solvent for multiple times, and finally dried in a vacuum drying box for 12h. Denoted as SiO2-COOH. d. Acyl chloride silica: the carboxylated silica is added into toluene at a mass-volume ratio of 1:10-40, and then oxalyl chloride is added at a mass-volume ratio of 1:0.5-10, and reacted at 20-50°C for 2-10h, and then reacted at 50-100°C for 1-4h. After the reaction is completed, the product is washed with a solvent for multiple times, and finally dried in a vacuum drying box for 12h. Denoted as SiO2-COCl. e. Dehydroabietic acid locust bean gum ester bonding silica: the acyl chloride silica is added into pyridine at a mass-volume ratio of 1:10-40, and then dehydroabietic acid locust bean gum ester with a certain degree of substitution is added, and the mass feeding ratio of the dehydroabietic acid locust bean gum ester to the acyl chloride silica is 1:0.1-20. Stirred and reacted at 40-120°C for 4-24h under an inert gas atmosphere. The product is washed with a solvent for multiple times, and finally dried in a vacuum drying box for 12h. Denoted as DLE@SiO231. f. After the reaction in step e is completed, a blocking agent is added into the system to continue the reaction for 1h. The product is washed with a solvent for multiple times, and finally dried in a vacuum drying box for 12h. Denoted as DLE@SiO231M.

4. The method for preparing dehydroabietic acid-locust bean gum ester-bonded silica microspheres according to claim 3, characterized by: The degree of substitution of the dehydroabietic acid locust bean gum ester is 0.001-2.

5.

5. The method of preparing dehydroabietic acid-locust bean gum ester-bonded silica microspheres according to claim 3, characterized by: The inert gas is nitrogen or argon.

6. The method of preparing dehydroabietic acid-locust bean gum ester-bonded silica microspheres according to claim 3, characterized by: The preparation method comprises the step of washing with a solvent for multiple times, and the solvent is pyridine or methanol or acetone or anhydrous diethyl ether.

7. The method of preparing dehydroabietic acid-locust bean gum ester-bonded silica microspheres according to claim 3, characterized by: The blocking agent is methanol or ethanol or propanol or butanol.

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