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...

Examples

Embodiment 1

[0034] A method of coating nano-starch microspheres by atomic layer deposition, surface modification of nano-starch microspheres with a particle size of 20nm, coating 5nm Fe 2 o 3 Thin films and 1nm Al 2 o 3 Thin film, where C is selected 10 h 10 Fe / O 3 , Al(CH 3 ) 3 / H 2 O is a precursor, which specifically includes the following steps:

[0035] (1) Iron oxide coating:

[0036] 1.1 After passing the nano-starch microspheres through the 800-mesh screen, weigh 5 mg and place it in the powder container of the atomic layer deposition equipment, put the powder container into the cavity, and evacuate to 10Pa;

[0037]1.2 Turn on the ultrasonic vibration, set the ultrasonic frequency to 20KHz, the working time of the ultrasonic vibration is 60s, and the intermittent time is 5s;

[0038] 1.3 Heat the cavity, and at the same time, feed the carrier gas to clean the surface of the nano-starch microspheres for 30 minutes and disperse them. The flow rate of the carrier gas is se...

Embodiment 2

[0053] A method of coating nano-starch microspheres by atomic layer deposition, surface modification of nano-starch microspheres with a particle size of 20nm, coating 5nm Fe 2 o 3 Thin films and 1nm Al 2 o 3 Thin film, where C is selected 10 h 10 Fe / O 3 , Al(CH 3 ) 3 / H 2 O is a precursor, which specifically includes the following steps:

[0054] (1) Iron oxide coating:

[0055] 1.1 After passing the nano starch microspheres through the 800 mesh screen, weigh 100g and place it in the powder container of the atomic layer deposition equipment, put the powder container into the cavity, and evacuate to 10Pa;

[0056] 1.2 Turn on the ultrasonic vibration, set the ultrasonic frequency to 40KHz, the working time of the ultrasonic vibration is 5min, and the intermittent time is 5s;

[0057] 1.3 Heat the cavity, and at the same time, pass the carrier gas to clean the surface of the nano-starch microspheres for 50 minutes and disperse them, and select the flow rate of the carr...

Embodiment 3

[0072] A method of coating nano-starch microspheres by atomic layer deposition, surface modification of nano-starch microspheres with a particle size of 10 μm, and coating with 5nm Fe 2 o 3 Thin films and 1nm SiO 2 Thin film, where C is selected 10 h 10 Fe / O 3 、SiCl 4 / H 2 O is a precursor, which specifically includes the following steps:

[0073] (1) Iron oxide coating:

[0074] 1.1 After passing the nano starch microspheres through the 800 mesh screen, weigh 200g and place it in the powder container of the atomic layer deposition equipment, put the powder container into the cavity, and evacuate to 10Pa;

[0075] 1.2 Turn on the ultrasonic vibration, set the ultrasonic frequency to 40KHz, the working time of the ultrasonic vibration is 10min, and the intermittent time is 5s;

[0076] 1.3 Heat the cavity, and at the same time pass the carrier gas to clean the surface of the nano-starch microspheres for 50 minutes and disperse them. The flow rate of the carrier gas is s...

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...

Examples

Embodiment 1

[0034] A method of coating nano-starch microspheres by atomic layer deposition, surface modification of nano-starch microspheres with a particle size of 20nm, coating 5nm Fe 2 o 3 Thin films and 1nm Al 2 o 3 Thin film, where C is selected 10 h 10 Fe / O 3 , Al(CH 3 ) 3 / H 2 O is a precursor, which specifically includes the following steps:

[0035] (1) Iron oxide coating:

[0036] 1.1 After passing the nano-starch microspheres through the 800-mesh screen, weigh 5 mg and place it in the powder container of the atomic layer deposition equipment, put the powder container into the cavity, and evacuate to 10Pa;

[0037]1.2 Turn on the ultrasonic vibration, set the ultrasonic frequency to 20KHz, the working time of the ultrasonic vibration is 60s, and the intermittent time is 5s;

[0038] 1.3 Heat the cavity, and at the same time, feed the carrier gas to clean the surface of the nano-starch microspheres for 30 minutes and disperse them. The flow rate of the carrier gas is se...

Embodiment 2

[0053] A method of coating nano-starch microspheres by atomic layer deposition, surface modification of nano-starch microspheres with a particle size of 20nm, coating 5nm Fe 2 o 3 Thin films and 1nm Al 2 o 3 Thin film, where C is selected 10 h 10 Fe / O 3 , Al(CH 3 ) 3 / H 2 O is a precursor, which specifically includes the following steps:

[0054] (1) Iron oxide coating:

[0055] 1.1 After passing the nano starch microspheres through the 800 mesh screen, weigh 100g and place it in the powder container of the atomic layer deposition equipment, put the powder container into the cavity, and evacuate to 10Pa;

[0056] 1.2 Turn on the ultrasonic vibration, set the ultrasonic frequency to 40KHz, the working time of the ultrasonic vibration is 5min, and the intermittent time is 5s;

[0057] 1.3 Heat the cavity, and at the same time, pass the carrier gas to clean the surface of the nano-starch microspheres for 50 minutes and disperse them, and select the flow rate of the carr...

Embodiment 3

[0072] A method of coating nano-starch microspheres by atomic layer deposition, surface modification of nano-starch microspheres with a particle size of 10 μm, and coating with 5nm Fe 2 o 3 Thin films and 1nm SiO 2 Thin film, where C is selected 10 h 10 Fe / O 3 、SiCl 4 / H 2 O is a precursor, which specifically includes the following steps:

[0073] (1) Iron oxide coating:

[0074] 1.1 After passing the nano starch microspheres through the 800 mesh screen, weigh 200g and place it in the powder container of the atomic layer deposition equipment, put the powder container into the cavity, and evacuate to 10Pa;

[0075] 1.2 Turn on the ultrasonic vibration, set the ultrasonic frequency to 40KHz, the working time of the ultrasonic vibration is 10min, and the intermittent time is 5s;

[0076] 1.3 Heat the cavity, and at the same time pass the carrier gas to clean the surface of the nano-starch microspheres for 50 minutes and disperse them. The flow rate of the carrier gas is s...

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