Magnetic iron oxide-dendritic polyamide core-shell nano complex and preparation thereof

Abstract

The invention relates to a magnetic iron oxide-dendritic polyamide core-shell nano complex and preparation thereof. The whole generation of dendritic polyamide is adopted as a spherical shell-shaped external framework, the interior is magnetic iron oxide, wherein the whole generation of dendritic polyamide accounts for 5 to 15 percent by weight, the whole generation of dendritic polyamide and the magnetic iron oxide are combined by the method of chemical coupling, the rigid framework of the dendritic polyamid effectively prevents the aggregation of magnetic nano particles, and thereby the stability of the intracorporeal circulation of carrier complex is enhanced; in addition, only the amino-group on the surface of the polyamide molecule electrostatically interacts with DNA, the parahelium group inside the polyamide molecule can neutralize the acidity of the inclusion body, consequently, the collapse of the inclusion body can be promoted, DNA can be released out of the inclusion body, and thereby the expression of DNA in cells in vivo can be improved.

Description

[0001] This application is a divisional application of the invention application: "A Novel Magnetic Targeting Gene Delivery System and Its Preparation". The application number of the original application is: 200710158236.8, and the filing date is November 13, 2007. technical field

[0002] The invention relates to a magnetic iron oxide-dendritic polyamide core-shell nanocomposite and its preparation. Background technique

[0003] Magnetic nanoparticles have attracted extensive attention for applications in biomacromolecule separation, magnetic resonance imaging, biolabeling, and targeted drug delivery. Dendrimer is a new type of nanoscale macromolecule artificially synthesized in recent years. Its highly branched, monodisperse, a large number of cavities inside the molecule and a large number of reactive groups on the spherical surface make it It has many properties and characteristics different from linear polymers. During the synthesis process of this new type of dendrime...

Examples

Embodiment 1

[0034] 1. Add 0.5M Fe 2+ and Fe 3+ solution, mixed in a molar ratio of 1:2, with a total volume of 30ml. At 75°C, under nitrogen protection, add dropwise to NH 3 -NH 4In the Cl buffer solution (pH=10, total volume 15ml), 10ml of concentrated ammonia water was added at the same time, and the reaction was terminated after 90min of magnetic stirring. After magnetic separation and distilled water washing, the product was redispersed in 1.0M sodium citrate solution, and mechanically stirred at 60°C for 12h. After the product is washed by magnetic separation, it is made into a 30 mg / ml water-based magnetic fluid.

[0035] 2. Secondary surface modification of magnetic fluid with silane coupling agent. Disperse 2ml of magnetic fluid in an alcohol-water mixture with a volume ratio of 4:1, then add 5ml of ammonia water and 0.01ml of tetraethylorthosilicate, and stir mechanically at 30°C for 12h. The product was magnetically separated, washed with anhydrous ethanol, acetone and anh...

Embodiment 2

[0047] 1. Add 0.5M Fe 2+ and Fe 3+ solution, mixed at a molar ratio of 1:1, with a total volume of 30ml. At 55°C, under nitrogen protection, add dropwise to NH 3 -NH 4 In the Cl buffer solution (pH=9, total volume 15ml), 10ml of concentrated ammonia water was added at the same time, and the reaction was terminated after magnetic stirring for 60min. After magnetic separation and distilled water washing, the product was redispersed in 1.0M sodium citrate solution, and mechanically stirred at 60°C for 12h. After the product is washed by magnetic separation, it is made into a 30 mg / ml water-based magnetic fluid.

[0048] 2. Secondary surface modification of magnetic fluid with silane coupling agent. Disperse 2ml of magnetic fluid in an alcohol-water mixture with a volume ratio of 4:1, then add 5ml of ammonia water and 0.01ml of tetraethylorthosilicate, and stir mechanically at 30°C for 10h. After the product was magnetically separated, washed with absolute ethanol, acetone a...

Embodiment 3

[0053] 1. Add 0.5M Fe 2+ and Fe 3+ solution, mixed at a molar ratio of 1:1, with a total volume of 30ml. At 60°C, under the protection of nitrogen, add dropwise to NH 3 -NH 4 In the Cl buffer solution (pH = 11, total volume 15 ml), 10 ml of concentrated ammonia water was added at the same time, and the reaction was terminated after magnetic stirring for 60 min. After magnetic separation and distilled water washing, the product was redispersed in 1.0M sodium citrate solution, and mechanically stirred at 60°C for 12h. After the product is washed by magnetic separation, it is made into a 30 mg / ml water-based magnetic fluid.

[0054] 2. Secondary surface modification of magnetic fluid with silane coupling agent. Disperse 2ml of magnetic fluid in an alcohol-water mixture with a volume ratio of 4:1, then add 5ml of ammonia water and 0.01ml of tetraethylorthosilicate, and stir mechanically at 30°C for 12h. After the product was magnetically separated, washed with absolute ethan...

[0001] This application is a divisional application of the invention application: "A Novel Magnetic Targeting Gene Delivery System and Its Preparation". The application number of the original application is: 200710158236.8, and the filing date is November 13, 2007. technical field

[0002] The invention relates to a magnetic iron oxide-dendritic polyamide core-shell nanocomposite and its preparation. Background technique

[0003] Magnetic nanoparticles have attracted extensive attention for applications in biomacromolecule separation, magnetic resonance imaging, biolabeling, and targeted drug delivery. Dendrimer is a new type of nanoscale macromolecule artificially synthesized in recent years. Its highly branched, monodisperse, a large number of cavities inside the molecule and a large number of reactive groups on the spherical surface make it It has many properties and characteristics different from linear polymers. During the synthesis process of this new type of dendrime...

Examples

Embodiment 1

[0034] 1. Add 0.5M Fe 2+ and Fe 3+ solution, mixed in a molar ratio of 1:2, with a total volume of 30ml. At 75°C, under nitrogen protection, add dropwise to NH 3 -NH 4In the Cl buffer solution (pH=10, total volume 15ml), 10ml of concentrated ammonia water was added at the same time, and the reaction was terminated after 90min of magnetic stirring. After magnetic separation and distilled water washing, the product was redispersed in 1.0M sodium citrate solution, and mechanically stirred at 60°C for 12h. After the product is washed by magnetic separation, it is made into a 30 mg / ml water-based magnetic fluid.

[0035] 2. Secondary surface modification of magnetic fluid with silane coupling agent. Disperse 2ml of magnetic fluid in an alcohol-water mixture with a volume ratio of 4:1, then add 5ml of ammonia water and 0.01ml of tetraethylorthosilicate, and stir mechanically at 30°C for 12h. The product was magnetically separated, washed with anhydrous ethanol, acetone and anh...

Embodiment 2

[0047] 1. Add 0.5M Fe 2+ and Fe 3+ solution, mixed at a molar ratio of 1:1, with a total volume of 30ml. At 55°C, under nitrogen protection, add dropwise to NH 3 -NH 4 In the Cl buffer solution (pH=9, total volume 15ml), 10ml of concentrated ammonia water was added at the same time, and the reaction was terminated after magnetic stirring for 60min. After magnetic separation and distilled water washing, the product was redispersed in 1.0M sodium citrate solution, and mechanically stirred at 60°C for 12h. After the product is washed by magnetic separation, it is made into a 30 mg / ml water-based magnetic fluid.

[0048] 2. Secondary surface modification of magnetic fluid with silane coupling agent. Disperse 2ml of magnetic fluid in an alcohol-water mixture with a volume ratio of 4:1, then add 5ml of ammonia water and 0.01ml of tetraethylorthosilicate, and stir mechanically at 30°C for 10h. After the product was magnetically separated, washed with absolute ethanol, acetone a...

Embodiment 3

[0053] 1. Add 0.5M Fe 2+ and Fe 3+ solution, mixed at a molar ratio of 1:1, with a total volume of 30ml. At 60°C, under the protection of nitrogen, add dropwise to NH 3 -NH 4 In the Cl buffer solution (pH = 11, total volume 15 ml), 10 ml of concentrated ammonia water was added at the same time, and the reaction was terminated after magnetic stirring for 60 min. After magnetic separation and distilled water washing, the product was redispersed in 1.0M sodium citrate solution, and mechanically stirred at 60°C for 12h. After the product is washed by magnetic separation, it is made into a 30 mg / ml water-based magnetic fluid.

[0054] 2. Secondary surface modification of magnetic fluid with silane coupling agent. Disperse 2ml of magnetic fluid in an alcohol-water mixture with a volume ratio of 4:1, then add 5ml of ammonia water and 0.01ml of tetraethylorthosilicate, and stir mechanically at 30°C for 12h. After the product was magnetically separated, washed with absolute ethan...

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