Preparation for magnetic nanoparticle with breakable oxygen ammonia functional groups and application to separation and enrichment of glycoprotein

[0024] Example 1

[0025] Preparation of magnetic nanoparticles with surface amino-modified core-shell structure:

[0026] 1. Synthesis of Magnetic Nanoparticles by Co-precipitation

[0027] Take Fe respectively 3+ , Fe 2+ Dissolve in 80ml double distilled water, Fe 3+ , Fe 2+ The total concentration of 0.1g / ml, Fe 3+ : Fe 2+ The molar ratio is 1:1,75 O C. Stir and react at 1000r / min for 20min, add 5ml of ammonia water dropwise, and maintain pH 10.0, react for 1 hour after the dropwise addition, mix with ultrasonic, wash with water 2-3 times, magnetically separate, and freeze-dry to obtain magnetic nanoparticles.

[0028] 2. SiO 2 Encapsulated Magnetic Nanoparticles

[0029] Utilizing the inverse microemulsion method, in the water-in-oil environment, tetraethyl orthosilicate is solvent-formed into silicon balls, and the magnetic nanoparticles are wrapped. In 50ml of ethanol, add 300mg of nanoparticles obtained in the previous step and 2ml of tetraethyl orthosilicate

[0034] Example 2

[0035] Synthesis of cleavable oxyaminosilanes:

[0036] Weigh 10g of 9-fluorenyloxycarbonylaminoacetic acid, 5g of pyridine dithiocysteine ​​hydrochloride and 100ml of acetonitrile, add alkali and condensation agent PyBOP, react overnight at room temperature, and obtain the intermediate by column chromatography. The intermediate is reacted with mercaptopropionic acid at room temperature and separated by column chromatography, and the product obtained is condensed with 3-aminopropyltriethylsilane APTES to obtain a cleavable oxyaminosilane compound containing 9-fluorenyloxycarbonyl protected oxygen group . The synthesis route of the specific compound is as follows: Figure 5 .

[0037] Example 3

[0038] Preparation of Magnetic Nanoparticles with Surface Amino-modified Core-Shell Structure

[0039] 1. Synthesis of Magnetic Nanoparticles by Co-precipitation

[0040] Take Fe respectively 3+ ,Fe 2+ Dissolve in 80ml double distilled water, Fe 3+ , Fe 2+ The total concentration of 0.1g / ml, Fe 3+ : Fe 2+ The molar ratio is 1:1,75 O C. Stir and react at 1000r / min for 20min, add 5ml of ammonia water dropwise, and maintain pH 10.0, react for 1 hour after the dropwise addition, mix with ultrasonic, wash with water 2-3 times, magnetically separate, and freeze-dry to obtain magnetic nanoparticles.

[0041] 2. SiO 2 Encapsulated Magnetic Nanoparticles

[0042]Utilizing the inverse microemulsion method, in the water-in-oil environment, tetraethyl orthosilicate is solvent-formed into silicon balls, and the magnetic nanoparticles are wrapped. In 50ml of ethanol, add tetraethyl orthosilicate (TEOS) and stir for 2 hours, add 5ml of ammonia water drop by drop