Method for cladding nanometer starch microspheres through atomic layer deposition

Abstract

The invention belongs to the technical field of nanometer starch microsphere modification, and particularly relates to a method for cladding nanometer starch microspheres through atomic layer deposition. The nanometer starch microspheres are placed into an ultrasonic vertical fluidizing atomic layer deposition device, ultrasonic vibration is started, under a proper reaction temperature and pressure, properly-active and vapor-pressure precursors are selected to be alternately introduced, a single layer of chemical adsorption is formed and self-limiting chemical semi-reaction is completed on thesurfaces of the nanometer starch microspheres through exchanging of active functional groups to generate compact thin films, and cladding is performed on all the parts of the surfaces through the thin films with uniform and consistent thickness. The nanometer thin films generated through an atomic layer deposition technology are high in cladding uniformity, especially uniform cladding can be performed on the small-grained nanometer starch microspheres, the formed nanometer thin films are compact in structure and have the uniform thickness and excellent consistency, and due to the characteristics of a reacting mechanism of the thin films, the cladding of the nanometer starch microspheres of different grain sizes can be realized.

Description

technical field [0001] The invention belongs to the technical field of modification of nano-starch microspheres, relates to a method for surface modification of nano-starch microspheres, in particular to a method for coating nano-starch microspheres by atomic layer deposition. Background technique [0002] As a drug carrier, magnetic starch microspheres can use an external magnetic field to guide their directional movement and concentration in the body, so that the drug can be selectively distributed in specific organs, tissues or cells, so as to achieve the purpose of directional action on the target tissue. Increase the drug concentration in the diseased tissue, improve the utilization rate of the drug, and reduce or eliminate the toxic and side effects of the drug on the normal tissue. However, as a drug carrier, nano-starch microspheres still have insufficient adsorption force between the drug and the starch surface, and are prone to biological contamination at room temp...

AI Technical Summary

Problems solved by technology

The present invention utilizes atomic layer deposition equipment to select precursors with suitable activity and vapor pressure to alternately pass in under appropriate reaction temperature and pressure, and forms a single-layer chemical adsorption on the surface of nano starch microspheres through the exchange of active functional groups and completes self-limiting chemistry. Half-reaction, the deposited substance can be plated layer by layer on the surface of nano starch microspheres in the form of a monoatomic film on the nanometer scale, and the various parts of the surface can be coated with a film of uniform thickness, which can solve the current nano Starch microspheres are easy to be infected by organisms when exposed to light and water, low magnetic content, and difficult to control the particle size of magnetic particles. The formed nano-scale film does not affect the surface adsorption performance and biodegradability of nano-starch microspheres.

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