(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.