COLLOIDOSOME WITH VARIABLE PORE SIZE AND PREPARATION METHOD THEREOF

Abstract

A colloidosome with a variable pore size and a preparation method thereof are provided. The preparation method includes the steps of modification of nanoparticles, preparation of amphiphilic nanoparticles, preparation of a colloidosome with a variable pore size and the like. Through specific setting of each step, the finally prepared colloidosome is stable and has a variable pore size, and a hydrophobic polymer chain in a cavity of the colloidosome has corresponding contraction and extension forms in different medium environments, such as water and oil, to block or expose pores, so as to meet application requirements for transmission in selective media.

Claims

1. A method for preparing a colloidosome with a variable pore size, wherein the colloidosome is prepared by subjecting amphiphilic composite nanoparticles to water-oil two-phase emulsion and assembly at an interface to obtain a micelle, followed by crosslinking based on a template method, and wherein the colloidosome has a diameter of 1-15 ?m; pores of the colloidosome are generated by stacking adjacent amphiphilic composite nanoparticles, and the variable pore size is controlled by changing a concentration and/or a number of the adjacent amphiphilic composite nanoparticles, wherein the colloidosome has a minimum pore size when the adjacent amphiphilic composite nanoparticles are stacked in a form of hexagonal close packing, wherein the pore with the minimum pore size has an area of (0.03-0.05)?d.sup.2 nm.sup.2, and wherein d refers to a diameter of each of the amphiphilic composite nanoparticles.

2. The method for preparing the colloidosome with the variable pore size according to claim 1, comprising the following steps: (1) modification of the amphiphilic composite nanoparticles: subjecting inorganic nanoparticles with a diameter or an equivalent diameter of 10-150 nm to surface modification by a silane ligand exchange method to enable surfaces of the inorganic nanoparticles modified with amino and/or carboxyl so as to form modified nanoparticles; (2) synthesis of a polymer chain: performing cationic polymerization with a boron trifluoride-ether complex as an initiator in an ultra-dry dichloromethane solvent to prepare an active polymer chain solution; (3) preparation of amphiphilic single-chain nanoparticles: dispersing the modified nanoparticles prepared in step (1) in ultra-dry dichloromethane to obtain a modified nanoparticle dispersion solution; slowly adding the active polymer chain solution prepared in step (2) into the modified nanoparticle dispersion solution under ultrasonic conditions, wherein a volume-mass ratio of the active polymer chain solution to the modified nanoparticles is (0.9-1) mL:(0.9-1) mg; and performing ultrasonic treatment continuously to carry out a reaction for 0.8-1.5 h, then performing solid-liquid separation with a magnet, and washing a solid to obtain single-chain nanoparticles; and (4) preparation of the colloidosome with the variable pore size: placing 990-1,010 parts by weight of a water phase, 98-102 parts by weight of an oil phase and 0.8-1.2 parts by weight of the single-chain nanoparticles prepared in step (3) in a container, and performing emulsification to obtain a uniform oil-in-water emulsion; then adding glacial acetic acid to adjust a pH of the water phase to 4.8-5.2, and performing crosslinking with a glutaraldehyde aqueous solution, wherein a mass ratio of the glutaraldehyde aqueous solution to the single-chain nanoparticles is (1.2-1.5):1; and after a dynamic Schiff base bond is formed in a reaction at room temperature for 4-6 h, performing reduction with sodium borohydride to obtain the colloidosome with the variable pore size, wherein a mass ratio of the sodium borohydride to the glutaraldehyde aqueous solution is (0.5-1):1.

3. The method for preparing the colloidosome with the variable pore size according to claim 2, wherein in step (1), the inorganic nanoparticles are SiO.sub.2 nanoparticles, the modified nanoparticles obtained in step (1) are SiO.sub.2@NH.sub.2 nanoparticles, and step (1) comprises: treating the SiO.sub.2 nanoparticles with amino silane for silane ligand exchange with the glacial acetic acid as a catalyst in a non-polar solvent, wherein a volume ratio of the inorganic nanoparticles to the amino silane to the catalyst is 0.02% (m/v):0.5% (v/v):0.01% (v/v) in the non-polar solvent.

4. The method for preparing the colloidosome with the variable pore size according to claim 3, wherein the non-polar solvent is toluene or n-hexane; and the amino silane is 3-aminopropyltrimethoxysilane and/or 3-aminopropyltriethoxysilane.

5. The method for preparing the colloidosome with the variable pore size according to claim 2, wherein in step (2), the active polymer chain solution is an active hydrophobic polymer and comprises one or more of polystyrenes and polyolefins; a hydrodynamic diameter of the active hydrophobic polymer is equal to or greater than 80% of a diameter of the inorganic nanoparticles, and the active hydrophobic polymer has a weight-average molecular weight of 3.5?10.sup.1-3?10.sup.3 kDa; and the ultrasonic conditions in step (3) comprise an ultrasonic frequency of 55-62 KHz and an ultrasonic temperature of 23-28? C.

6. The method for preparing the colloidosome with the variable pore size according to claim 5, wherein the polystyrenes and the polyolefins comprise poly(p-methylstyrene) or polyisobutylene.

7. The method for preparing the colloidosome with the variable pore size according to claim 2, wherein in step (4), the water phase comprises water, and the oil phase comprises dichloromethane, toluene or sliced paraffin with a melting point of 52-54? C.

8. The method for preparing the colloidosome with the variable pore size according to claim 2, wherein in step (4), the uniform oil-in-water emulsion is obtained by using sliced paraffin as the oil phase, and the step comprises: placing the container in hot water to perform ultrasonic treatment at 60-70? C., stopping the ultrasonic treatment after the sliced paraffin is completely melted, keeping a heating temperature at 60-70? C. continuously, and then subjecting a resulting mixture to high-speed shearing by using a high-speed shearing machine at a shearing rate of 10,000-15,000 rmp/min for 2-4 min to prepare the uniform oil-in-water emulsion floating on an upper layer of the water phase.

9. The method for preparing the colloidosome with the variable pore size according to claim 8, wherein after the uniform oil-in-water emulsion is obtained in step (4), the uniform oil-in-water emulsion is subjected to standing and cooled to room temperature until being solidified to obtain a cooled colloidosome with the variable pore size; and the cooled colloidosome with the variable pore size is immersed in n-hexane for 30-60 min and then taken out to obtain the colloidosome with the variable pore size, wherein the colloidosome with the variable pore size is a hollow sphere with dissolved paraffin, and wherein the n-hexane is added in an amount to ensure the cooled colloidosome to be completely immersed.

10. A colloidosome with a variable pore size, wherein the colloidosome is prepared by the method according to claim 1; and a hydrophobic polymer chain in a cavity of the colloidosome with the variable pore size has contraction and extension forms in different medium environments, wherein the medium environments comprise water and/or oil, wherein the hydrophobic polymer chain is configured to block or expose pores, and wherein the colloidosome is applied to transmission in selective media.

11. The colloidosome with the variable pore size according to claim 10, wherein the colloidosome is prepared by the method comprising the following steps: (1) modification of the amphiphilic composite nanoparticles: subjecting inorganic nanoparticles with a diameter or an equivalent diameter of 10-150 nm to surface modification by a silane ligand exchange method to enable surfaces of the inorganic nanoparticles modified with amino and/or carboxyl so as to form modified nanoparticles; (2) synthesis of a polymer chain: performing cationic polymerization with a boron trifluoride-ether complex as an initiator in an ultra-dry dichloromethane solvent to prepare an active polymer chain solution; (3) preparation of amphiphilic single-chain nanoparticles: dispersing the modified nanoparticles prepared in step (1) in ultra-dry dichloromethane to obtain a modified nanoparticle dispersion solution; slowly adding the active polymer chain solution prepared in step (2) into the modified nanoparticle dispersion solution under ultrasonic conditions, wherein a volume-mass ratio of the active polymer chain solution to the modified nanoparticles is (0.9-1) mL:(0.9-1) mg; and performing ultrasonic treatment continuously to carry out a reaction for 0.8-1.5 h, then performing solid-liquid separation with a magnet, and washing a solid to obtain single-chain nanoparticles; and (4) preparation of the colloidosome with the variable pore size: placing 990-1,010 parts by weight of a water phase, 98-102 parts by weight of an oil phase and 0.8-1.2 parts by weight of the single-chain nanoparticles prepared in step (3) in a container, and performing emulsification to obtain a uniform oil-in-water emulsion; then adding glacial acetic acid to adjust a pH of the water phase to 4.8-5.2, and performing crosslinking with a glutaraldehyde aqueous solution, wherein a mass ratio of the glutaraldehyde aqueous solution to the single-chain nanoparticles is (1.2-1.5): 1; and after a dynamic Schiff base bond is formed in a reaction at room temperature for 4-6 h, performing reduction with sodium borohydride to obtain the colloidosome with the variable pore size, wherein a mass ratio of the sodium borohydride to the glutaraldehyde aqueous solution is (0.5-1):1.

12. The colloidosome with the variable pore size according to claim 11, wherein wherein in step (1) of the method for preparing the colloidosome, the inorganic nanoparticles are SiO.sub.2 nanoparticles, the modified nanoparticles obtained in step (1) are SiO.sub.2@NH.sub.2 nanoparticles, and step (1) comprises: treating the SiO.sub.2 nanoparticles with amino silane for silane ligand exchange with the glacial acetic acid as a catalyst in a non-polar solvent, wherein a volume ratio of the inorganic nanoparticles to the amino silane to the catalyst is 0.02% (m/v):0.5% (v/v):0.01% (v/v) in the non-polar solvent.

13. The colloidosome with the variable pore size according to claim 12, wherein the non-polar solvent is toluene or n-hexane; and the amino silane is 3-aminopropyltrimethoxysilane and/or 3-aminopropyltriethoxysilane.

14. The colloidosome with the variable pore size according to claim 11, wherein in step (2) of the method for preparing the colloidosome, the active polymer chain solution is an active hydrophobic polymer and comprises one or more of polystyrenes and polyolefins; a hydrodynamic diameter of the active hydrophobic polymer is equal to or greater than 80% of a diameter of the inorganic nanoparticles, and the active hydrophobic polymer has a weight-average molecular weight of 3.5?10.sup.1-3?10.sup.3 kDa; and the ultrasonic conditions in step (3) comprise an ultrasonic frequency of 55-62 KHz and an ultrasonic temperature of 23-28? ? C.

15. The colloidosome with the variable pore size according to claim 14, wherein the polystyrenes and the polyolefins comprise poly(p-methylstyrene) or polyisobutylene.

16. The colloidosome with the variable pore size according to claim 11, wherein in step (4) of the method for preparing the colloidosome, the water phase comprises water, and the oil phase comprises dichloromethane, toluene or sliced paraffin with a melting point of 52-54? C.

17. The colloidosome with the variable pore size according to claim 11, wherein in step (4) of the method for preparing the colloidosome, the uniform oil-in-water emulsion is obtained by using sliced paraffin as the oil phase, and the step comprises: placing the container in hot water to perform ultrasonic treatment at 60-70? C., stopping the ultrasonic treatment after the sliced paraffin is completely melted, keeping a heating temperature at 60-70? C. continuously, and then subjecting a resulting mixture to high-speed shearing by using a high-speed shearing machine at a shearing rate of 10,000-15,000 rmp/min for 2-4 min to prepare the uniform oil-in-water emulsion floating on an upper layer of the water phase.

18. The colloidosome with the variable pore size according to claim 17, wherein after the uniform oil-in-water emulsion is obtained in step (4), the uniform oil-in-water emulsion is subjected to standing and cooled to room temperature until being solidified to obtain a cooled colloidosome with the variable pore size; and the cooled colloidosome with the variable pore size is immersed in n-hexane for 30-60 min and then taken out to obtain the colloidosome with the variable pore size, wherein the colloidosome with the variable pore size is a hollow sphere with dissolved paraffin, and wherein the n-hexane is added in an amount to ensure the cooled colloidosome to be completely immersed.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG. 1 is a schematic diagram of a preparation process of a colloidosome with a variable pore size described in the present invention.

[0028] FIG. 2 is a scanning electron microscope (SEM) photograph of a colloidosome with a variable pore size prepared in Example 1 of the present invention.

[0029] FIG. 3 is an SEM photograph of a colloidosome with a variable pore size prepared in Example 2 of the present invention.

[0030] FIG. 4 is a transmission electron microscope (TEM) photograph of the colloidosome with a variable pore size prepared in Example 2 of the present invention.

DETAINED DESCRIPTION OF THE EMBODIMENTS

[0031] To clarify the technical problems addressed, technical schemes, and the advantages of the present invention, a detailed description is provided below, accompanied by attached drawings and specific embodiments.

Example 1

[0032] The present example provides a silica colloidosome with a variable pore size of the present invention, where sliced paraffin is used as a template, and the colloidosome has a size of about 10 ?m. A schematic diagram of a preparation process is shown in FIG. 1. A preparation method specifically includes the following steps.

(1) Synthesis of SiO.SUB.2.@NH.SUB.2 .Nanoparticles

[0033] An aqueous solution of SiO.sub.2 nanoparticles with a diameter of 12 nm was freeze-dried for later use. 150 ?L of 3-aminopropyltriethoxysilane and 3 ?L of acetic acid were added into a toluene dispersion solution (30 mL) containing 6 mg of SiO.sub.2 nanoparticles, and stirred to carry out a reaction at room temperature for 24 h. Then, a resulting solution was washed with toluene, centrifuged and separated at high speed, and freeze-dried for later use.

(2) Synthesis of a Poly(p-Methylstyrene) (PMS) Chain

[0034] 20 ?L of a boron trifluoride-ether complex was added into 10 mL of ultra-dry dichloromethane, and 3 mL of a p-methylstyrene monomer was added under magnetic stirring to carry out a reaction at room temperature for 30 min so as to synthesize a PMS polymer chain with a molecular weight of 40.9 kDa, where the size (hydrodynamic diameter) of the chain was equivalent to the diameter of the SiO.sub.2@NH.sub.2 particles.

(3) Preparation of PMS-SiO.SUB.2.@NH.SUB.2 .Amphiphilic Nanoparticles

[0035] 10 mg of SiO.sub.2@NH.sub.2 was dispersed in 10 mL of ultra-dry dichloromethane. Under ultrasonic conditions, an active PMS chain solution obtained in step (3) was slowly added to carry out an ultrasonic reaction for 1 h. Then, a resulting solution was washed with dichloromethane, centrifuged, and precipitated to obtain a product, marked as PMS-SiO.sub.2@NH.sub.2 particles.

(4) Preparation of a Colloidosome with a Variable Pore Size

[0036] 2 mg of the PMS-SiO.sub.2@NH.sub.2 particles obtained in step (3) were dispersed in 2 mL of water, 0.2 g of sliced paraffin (with a melting point of 52? C.) was added, a glass flask was placed in hot water for ultrasonic treatment at 70? C. until the paraffin was completely melted, and then a resulting solution was emulsified by a high-speed shearing emulsifier at a shearing rate of 10,000 rmp/min to obtain an emulsion floating on an upper layer of a water phase. Then, 0.2 mL of a glutaraldehyde aqueous solution was added into the emulsion, the pH of the water phase was adjusted to 5, and the mixed solution was reduced with sodium borohydride after a dynamic Schiff base bond was formed. Finally, the mixed solution was soaked in 5 mL of n-hexane for 30 min and then taken out to obtain a colloidosome with a variable pore size. The structure of the prepared colloidosome was characterized by a scanning electron microscope.

[0037] The colloidosome is a sphere with a size of about 10 ?m, as shown in FIG. 2.

Example 2

[0038] The present example provides a silica colloidosome with a variable pore size of the present invention, where an emulsion drop is used as a template, and the colloidosome has a size of about 1 ?m. A preparation method specifically includes the following steps.

(1) Synthesis of SiO.SUB.2.@NH.SUB.2 .Nanoparticles (Modification of Nanoparticles)

[0039] An aqueous solution of SiO.sub.2 nanoparticles with a diameter of 12 nm was freeze-dried for later use. 150 ?L of 3-aminopropyltriethoxysilane and 3 ?L of acetic acid were added into a toluene dispersion solution (30 mL) containing 6 mg of SiO.sub.2 nanoparticles, and stirred to carry out a reaction at room temperature for 24 h. Then, a resulting solution was washed with toluene, centrifuged and separated at high speed, and freeze-dried for later use.

(2) Synthesis of a Poly(p-Methylstyrene) (PMS) Chain (Synthesis of a Polymer Chain)

[0040] 20 ?L of a boron trifluoride-ether complex was added into 10 mL of ultra-dry dichloromethane, and 3 mL of a p-methylstyrene monomer was added under magnetic stirring to carry out a reaction at room temperature for 30 min so as to synthesize a PMS polymer chain with a molecular weight of 40.9 kDa, where the size (hydrodynamic diameter) of the chain was equivalent to the diameter of the SiO.sub.2@NH.sub.2 particles.

(3) Preparation of PMS-SiO.SUB.2.@NH.SUB.2 .Amphiphilic Nanoparticles (Preparation of Amphiphilic Single-Chain Nanoparticles)

[0041] 10 mg of SiO.sub.2@NH.sub.2 was dispersed in 10 mL of ultra-dry dichloromethane. Under ultrasonic conditions, an active PMS chain solution obtained in step (3) was slowly added to carry out an ultrasonic reaction for 1 h. Then, a resulting solution was washed with dichloromethane, centrifuged, and precipitated to obtain a product, marked as PMS-SiO.sub.2@NH.sub.2 particles.

(4) Preparation of a Colloidosome with a Variable Pore Size

[0042] 2 mg of the PMS-SiO.sub.2@NH.sub.2 particles obtained in step (3) were dispersed in 2 mL of water, 0.2 mL of toluene was added, and then a resulting solution was emulsified to obtain an emulsion. Then, 0.2 mL of a glutaraldehyde aqueous solution was added into the emulsion, the pH of a water phase was adjusted to 5, and the mixed solution was reduced with sodium borohydride after a dynamic Schiff base bond was formed, so as to obtain a colloidosome with a variable pore size. The structure of the prepared colloidosome was characterized by a scanning electron microscope and a transmission electron microscope. The colloidosome is a sphere with a size of about 1 ?m, as shown in FIG. 3 and FIG. 4.

Example 3

[0043] The present example provides a magnetic responsive colloidosome with a variable pore size of the present invention, where an emulsion drop is used as a soft template, and the colloidosome has a size of about 2 ?m. A preparation method specifically includes the following steps.

(1) Synthesis of Fe.SUB.3.O.SUB.4 .Nanoparticles

[0044] 100 mL of a sodium oleate aqueous solution (0.2 M) and 100 mL of an anhydrous ferric chloride aqueous solution (0.2 M) were mixed and thoroughly stirred to produce a reddish-brown precipitate, and a mixed solution was filtered, rinsed with deionized water, and then dried in a vacuum oven. A dried waxy compound was dissolved in 60 mL of ethanol, uniformly mixed with 6 mL of oleic acid, and then transferred to a polytetrafluoroethylene high-pressure reactor to carry out a reaction at 180? C. for 5 h. A resulting mixture was washed with anhydrous ethanol, separated with a magnet, and dispersed in toluene for later use to obtain nanoparticles with a size of about 10 nm.

(2) Synthesis of Fe.SUB.3.O.SUB.4 .@NH.SUB.2 .Nanoparticles (Modification of Nanoparticles)

[0045] 0.5% (v/v) of 3-aminopropyltriethoxysilane and 0.01% (v/v) of acetic acid were added into a toluene dispersion solution (30 mL) containing 6 mg of Fe.sub.3O.sub.4 nanoparticles, and stirred to carry out a reaction at room temperature for 24 h. Then, a resulting solution was washed with toluene, separated with a magnet, and freeze-dried for later use.

(3) Synthesis of a Polyisobutylene (PIB) Chain (Synthesis of a Polymer Chain)

[0046] 20 ?L of a boron trifluoride-ether complex was added into 5 mL of ultra-dry dichloromethane, and 2 mL of an isobutylene monomer was added under magnetic stirring to carry out a reaction at room temperature for 30 min so as to synthesize a polyisobutylene polymer chain with a molecular weight of 34.3 kDa, where the size (hydrodynamic diameter) of the chain was equivalent to the diameter of the Fe.sub.3O.sub.4 @NH.sub.2 particles.

(4) Preparation of PIBFe.SUB.3.O.SUB.4 .@NH.SUB.2 .Amphiphilic Nanoparticles (Preparation of Amphiphilic Single-Chain Nanoparticles)

[0047] 10 mg of Fe.sub.3O.sub.4 @NH.sub.2 was dispersed in 10 mL of ultra-dry dichloromethane. Under ultrasonic conditions, an active PIB chain solution obtained in step (3) was slowly added to carry out an ultrasonic reaction for 1 h. Then, a resulting solution was washed with dichloromethane and collected with a magnet to obtain a product, marked as PIBFe.sub.3O.sub.4 @NH.sub.2 particles.

(5) Preparation of a Magnetic Responsive Colloidosome with a Variable Pore Size

[0048] 2 mg of the PIBFe.sub.3O.sub.4 @NH.sub.2 particles obtained in step (4) were dissolved in 2 mL of water, and 0.2 mL of toluene was added to carry out ultrasonic treatment for 1 min so as to obtain a uniform emulsion, where the emulsion has a size of about 2 ?m under a laser confocal microscope. Then, 0.2 mL of a glutaraldehyde aqueous solution was added into the obtained emulsion, the pH of a water phase was adjusted to 5, and the mixed solution was reduced with sodium borohydride after a dynamic Schiff base bond was formed, so as to obtain a magnetic responsive colloidosome with a variable pore size. The structure of the prepared colloidosome was characterized by a scanning electron microscope and a transmission electron microscope. The colloidosome is a hollow sphere with a size of about 2 ?m.

[0049] Technologies well-known in the field to which the present invention relates are not described in detail. The descriptions above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements and the like made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.