Hollow microcapsule, acidic or alkaline controlled-release microcapsule and preparation methods thereof

Abstract

The invention relates to a hollow microcapsule, an acidic or alkaline controlled-release microcapsule and preparation methods thereof, belonging to the field of biological agents. The preparation method of the hollow microcapsule comprises the following steps of: preparing a microcapsule through a layer-by-layer self-assembly method by taking calcium carbonate as a core and selecting polyelectrolyte cation and anion with opposite charges under a preparation condition; and then removing the core to obtain the hollow microcapsule. The wall of the hollow microcapsule is formed by alternating PAH / PSS (Polypropylene Amine hydrochloride / Poly Sodium Styrenesulfonate), and the hollow microcapsule can loaded with Cry protoxins of bacillus thuringiensis insecticidal crystal proteins under an acidic condition so as to obtain a microcapsule dosage form with release controlled under an alkaline condition. The microcapsule dosage form keeps the insecticidal activity of the cry protoxins, can assist the cry protoxins to resist the influence of certain environmental factors, also enables the insecticidal proteins to be specifically released in an alkaline environment of an insect midgut and keep stable in a general environment and plays an important role in the actual application of the Bt (Bacillus thuringiensis) insecticidal proteins on pest control.

Description

technical field [0001] The invention relates to the field of biological preparations, in particular to an empty microcapsule, an acidic or alkaline controlled-release microcapsule and a preparation method thereof. Background technique [0002] Bacillus thuringiensis (Bt) is a Gram-positive Agrobacterium belonging to the genus Bacillus, widely distributed in leaves, insect corpses, soil, storage dust, and sewage. It can produce paraspore crystals while forming spores, also known as insecticidal crystal proteins (Insecticidal Crystal Proteins, ICPs), parasitic on Lepidoptera, Diptera, Coleoptera, Hymenoptera, Homoptera insects and animals and plants Worm nematodes have specific poisoning effects, but are harmless to humans and livestock, and do not pollute the environment. They are widely used in agricultural and forestry pest control. [0003] Bacillus thuringiensis insecticidal crystal protein, also known as δ-endotoxin, is a kind of crystal protein with specific insecticid...

AI Technical Summary

Problems solved by technology

However, these studies are mainly aimed at the microencapsulation of Bacillus thuringiensis thallus, and the microencapsulation of insecticidal proteins has not been reported yet.

Moreover, the existing capsule dosage form does not have a long-lasting effect on bacterial protection, and the encapsulated content will be released into the environment as time goes by.

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