MICROBUBBLE DISPERSION SYSTEM STABILIZED WITH POLYDOPAMINE NANOPARTICLES FOR HIGHLY-EFFICIENT INTRAVENOUS OXYGEN SUPPLY AND METHOD FOR PREPARING THE SAME

Abstract

The present application discloses a microbubble dispersion system stabilized with polydopamine nanoparticles for highly-efficient intravenous oxygen supply and a method for preparing the same. The method includes: dissolving dopamine, chitosan quaternary ammonium salt and amino-rich polymer in water, adjusting the pH to be alkaline, and then introducing oxygen into the solution; under the strong shear force of a homogenizer, oxygen oxidizing dopamine, and the obtained polydopamine nanoparticles adhering to the interface of oxygen microbubbles during polymerization, forming a compact shell layer of polydopamine particles; finally, adding glutaraldehyde to solidify the shell layer of polydopamine particles adhered to the interface of microbubbles, and obtaining oxygen microbubbles stably dispersed in water by filtration, washing and redispersion. The oxygen microbubbles stabilized with polydopamine nanoparticles have excellent biocompatibility, can realize rapid and efficient delivery of oxygen, and thus have an important application value in the field of highly-efficient intravenous oxygen supply.

Claims

1. A method for preparing a microbubble dispersion system stabilized with polydopamine nanoparticles for highly-efficient intravenous oxygen supply, wherein the method comprising the following steps: (1) dissolving dopamine, a chitosan quaternary ammonium salt and polylysine in deionized water, and then adding a tris buffer solution to adjust a pH value of mixed solution to make the mixed solution alkaline; wherein a concentration of the dopamine is 10-40 mg/mL, a concentration of the polylysine is 1-40 mg/ml, and a concentration of the chitosan quaternary ammonium salt is 20-400 mg/ml; a mass ratio of the polylysine to the dopamine is 0.25-1; a mass ratio of the chitosan quaternary ammonium salt to the dopamine is 2-10; (2) introducing oxygen into the solution obtained in the step (1), shearing the oxygen into microbubbles by using a high-speed dispersion homogenizer, oxidizing and self-polymerizing the dopamine under alkaline conditions to form polydopamine nanoparticles, which adhere to an interface of the microbubbles to form a compact shell layer of polydopamine particles, then turning off the high-speed dispersion homogenizer, and continuously introducing oxygen until the solution is brownish black; (3) adding a glutaraldehyde solution into the solution obtained in the step (2), fully mixing by the high-speed dispersion homogenizer, and then stirring to solidify the shell layer of polydopamine particles adhered to the interface of the microbubbles; wherein a volume fraction of the glutaraldehyde solution is 2%-6.5%, and a dosage of the glutaraldehyde solution is 1 ml-5 ml; a rotating speed of the high-speed dispersion homogenizer is 10,000 rpm-14,000 rpm, and a homogenization time is 1-4 min; the stirring is carried out at 20-40° C. for 30 min-2 h; and (4) diluting a microbubble dispersion solution stabilized with the polydopamine nanoparticles obtain in the step (3), filtering and washing to remove redundant polydopamine nanoparticles and reagents which are not adhered on the interface of the microbubbles, and finally obtaining an oxygen microbubble dispersion system stabilized with the polydopamine nanoparticles stably dispersed in water.

2. The method for preparing a microbubble dispersion system stabilized with polydopamine nanoparticles according to claim 1, wherein in step (1), the adding a tris buffer solution to adjust a pH value of mixed solution to make the mixed solution alkaline is adding Tris-HCl to the mixed solution to adjust the pH value of the mixed solution to 7.5-9.0.

3. The method for preparing a microbubble dispersion system stabilized with polydopamine nanoparticles according to claim 1, wherein in the step (2), a flow rate of introducing oxygen is 0.5-2 L/min, a rotating speed of the high-speed dispersion homogenizer is 10,000 rpm-14,000 rpm, and a homogenization time is 3-6 min; introduction of oxygen is continued until the solution is brownish black.

4. The method for preparing a microbubble dispersion system stabilized with polydopamine nanoparticles according to claim 1, wherein in the step (4), a pore diameter of a filter paper is 1 μm-11 μm.

5. A microbubble dispersion system stabilized with polydopamine nanoparticles prepared by the method of any one of claims 1.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0023] FIG. 1 is a schematic diagram of a device for preparing a microbubble dispersion system stabilized with polydopamine nanoparticles;

[0024] FIG. 2 is a schematic diagram of the adhering and crosslinking solution of polydopamine nanoparticles at the oxygen-water interface in Example 1 of the present application;

[0025] FIG. 3A is an optical image of a microbubble dispersion solution stabilized with polydopamine nanoparticles obtained in step (3) in Example 1 of the present application;

[0026] FIG. 3B is an optical image of an oxygen microbubble dispersion stabilized with polydopamine nanoparticles obtained in step (4) in Example 1 of the present application;

[0027] FIG. 4 is the potential measurement of the microbubble dispersion liquid stabilized with polydopamine nanoparticles in Example 1 of the present application;

[0028] FIG. 5 is an optical image showing the time-varying morphology of the microbubbles stabilized with polydopamine nanoparticles in Example 2 of the present application;

[0029] FIG. 6A is a scanning electron microscope image of the microbubbles stabilized with polydopamine nanoparticles in Example 2 of the present application;

[0030] FIG. 6B is a scanning electron microscope image when the microbubbles stabilized with polydopamine nanoparticles collapse in Example 2 of the present application; and

[0031] FIG. 7 is a time-intensity curve of the oxygen release from the microbubbles stabilized with polydopamine nanoparticles in Example 3 of the present application in vitro.

DESCRIPTION OF EMBODIMENTS

[0032] The present application will be described with reference to the following examples, but the present application is not limited to the following examples.

Example 1

Preparation of an Oxygen Microbubble Dispersion System Stabilized with Polydopamine Nanoparticles

[0033] With reference to the device in FIG. 1, the oxygen microbubble dispersion system stabilized with polydopamine nanoparticles is prepared by the method of the present application, and the specific steps are as follows:

[0034] (1) 20 mg of dopamine, 5 mg of polylysine and 120 mg of a chitosan quaternary ammonium salt were dissolved in 10 mL of deionized water, and then 1 mL of a tris salt buffer solution with pH=8.5 was added to adjust the pH value of the mixed solution to make the mixed solution alkaline.

[0035] (2) Oxygen was introduced into the solution obtained in step (1) at a flow rate of 1 L/min, the rotating speed of a high-speed dispersion homogenizer was adjusted to 12000 rpm, and the oxygen was sheared into microbubbles by the homogenizer. The dopamine was oxidized and self-polymerized under alkaline conditions to form polydopamine nanoparticles, which adhered to the interface of microbubbles to form a compact shell layer of polydopamine particles (as shown in FIG. 2); the high-speed dispersion homogenizer was turned off after homogenizing for 5 min, and introduction of oxygen was continued for 2 min until the solution was brownish black.

[0036] (3) 1 ml of a 4% glutaraldehyde solution was added into the solution obtained in step (2), and the solution was homogenized with the high-speed dispersion homogenizer at 12000 rpm for 3 min, and then stirred at 1000 rpm for 30 min at room temperature to solidify the shell layer of polydopamine particles adhered to the interface of the microbubbles, thus obtaining a microbubble dispersion solution stabilized with polydopamine nanoparticles, as shown in FIG. 3A.

[0037] (4) The microbubble dispersion solution stabilized with polydopamine nanoparticles obtained in step (3) was diluted by deionized water for 5 times, and then the diluted solution was filtered with a filter paper with a pore size of 2.5 μm and a glass funnel to remove redundant polydopamine nanoparticles and other reagents not adsorbed on the interface of the microbubbles, then the microbubbles left on the filter paper were washed with deionized water and filtered again, and finally the microbubbles were flushed into glass bottles for storage with deionized water to obtain an oxygen microbubble dispersion solution stabilized with polydopamine nanoparticles stably dispersed in water, as shown in FIG. 3B. The surface of the microbubbles had a positive charge of +62.5 mV, which proved that there was a polydopamine shell layer on the surface of the microbubbles.

Example 2

Changes of Morphology of the Microbubbles Stabilized with Polydopamine Nanoparticles with Time

[0038] A dispersion liquid of microbubbles in water stabilized with polydopamine nanoparticles was stored at room temperature. The morphological changes of the microbubbles in water were regularly observed by an optical microscope, as shown in FIG. 5. A scanning electron microscope was used to observe the surface morphology of the microbubbles stabilized with polydopamine particles. As shown in FIG. 6A, there were compact nano-sized polydopamine particles at the interface of microbubbles. After standing and storing for one week, some microbubbles stabilized with polydopamine nanoparticles shrank or even collapsed, resulting in the release of oxygen wrapped in the shell layer of polydopamine nanoparticles, as shown in FIG. 6B.

Example 3

Oxygen Release Rate of Oxygen Microbubbles Stabilized with Polydopamine Nanoparticles In Vitro

[0039] (1) Under the condition of a room temperature of 20° C., the dissolved oxygen concentration of normal saline was reduced to Omg/L with pure N.sub.2 to prepare an extremely anoxic solution. Six hours after the successful preparation of the oxygen microbubbles stabilized with polydopamine nanoparticles, 1 ml of an oxygen-carrying microbubble dispersion liquid was injected into 10 ml of a sealed extremely anoxic solution, and the changes of the dissolved oxygen in the solution was detected by a dissolved oxygen analyzer; the release of O.sub.2 from the oxygen-carrying microbubbles in extremely anoxic saline was continually observed for about 30 min, as shown in FIG. 7. Oxygen microbubbles stabilized with polydopamine nanoparticles could effectively release O.sub.2 in the extremely anoxic saline, and 1 ml of the oxygen-carrying microbubble dispersion liquid could increase the dissolved oxygen content of the solution to about 5.5 mg/ml within 800 s, basically recovering to the saturated oxygen content in water.

[0040] (2) Under the condition of a room temperature of 20° C., the dissolved oxygen concentration of normal saline was reduced to 0 mg/L with pure N.sub.2 to prepare an extremely anoxic solution. Six hours after the successful preparation of the oxygen microbubbles stabilized with polydopamine nanoparticles, 2 ml of an oxygen-carrying microbubble dispersion liquid was injected into 10 ml of a sealed extremely anoxic solution, and the changes of the dissolved oxygen in the solution was detected by a dissolved oxygen analyzer; the release of O.sub.2 from the oxygen-carrying microbubbles in extremely anoxic saline was continually observed for about 30 min, as shown in FIG. 7. Oxygen microbubbles stabilized with polydopamine nanoparticles could effectively release O.sub.2 in the extremely anoxic saline, and 2 ml of the oxygen-carrying microbubble dispersion liquid could increase the dissolved oxygen content of the solution to about 5.5 mg/ml within 500 s, basically recovering to the saturated oxygen content in water.

[0041] (3) Under the condition of a room temperature of 20° C., the dissolved oxygen concentration of normal saline was reduced to Omg/L with pure N.sub.2 to prepare an extremely anoxic solution. Six hours after the successful preparation of the oxygen microbubbles stabilized with polydopamine nanoparticles, 3 ml of an oxygen-carrying microbubble dispersion liquid was injected into 10 ml of a sealed extremely anoxic solution, and the changes of the dissolved oxygen in the solution was detected by a dissolved oxygen analyzer; the release of O.sub.2 from the oxygen-carrying microbubbles in extremely anoxic saline was continually observed for about 30 min, as shown in FIG. 7. Oxygen microbubbles stabilized with polydopamine nanoparticles could effectively release O.sub.2 in the extremely anoxic saline, and 3 ml of the oxygen-carrying microbubble dispersion liquid could increase the dissolved oxygen content of the solution to about 5.5 mg/ ml within 200 s, basically recovering to the saturated oxygen content in water.