Polysaccharide/inorganic nanoparticles hybrid micron-nano medicine-carrying capsule

Abstract

The invention discloses polysaccharide / inorganic nanoparticles hybrid micron-nano medicine-carrying capsule. The capsule has the following structure characteristics: (1) a water in oil (W / O) microemulsion capsule core is prepared by using fat-soluble drug A or fat-soluble drug B which is dissolved in oily solvent, negative OSA modified polysaccharide derivative and water; (2) the polysaccharide and negative inorganic nanoparticles perform layer-by-layer self-assembly which is based on the electrostatic interaction to form a capsule wall; and (3) the grain size of the micron-nano medicine-carrying capsule is 50-1000nm. The micron-nano medicine-carrying capsule provided by the invention has high drug encapsulation efficiency for drug situ embedding, the raw materials are all adopted from biodegradable materials with good biocompatibility and biodegradability. In addition, the medicine-carrying system has double intelligent functions of targeting and controlled release.

Description

(1) Technical field [0001] The invention relates to a polymer / inorganic nanoparticle hybrid micronano drug-loaded capsule. (2) Background technology [0002] Therapeutic drugs, especially antineoplastic drugs, usually have strong toxic side effects on normal tissues and cells. Therefore, it is of great significance to target the delivery of drugs to the lesion and release them slowly, so as to reduce the distribution and release of drugs in normal tissues. The development of drug delivery system has become a research hotspot in the field of nanomedicine in recent years, and it is one of the ways to fundamentally change the therapeutic effect of drugs. [0003] The common carrier of fat-soluble drugs is liposome, which has a simple preparation process and is mainly formed spontaneously in water by phospholipids through hydrophobic association. Liposomes are thermodynamically unstable colloidal particles that are prone to spontaneous fusion and sedimentation; the membrane st...

AI Technical Summary

Problems solved by technology

[0007] The process of preparing pure polyelectrolyte capsules and polyelectrolyte / inorganic nanoparticle hybrid or pure inorganic nanoparticle capsules by the LbL method is generally as follows: first, the suspension of colloidal particles is added to an excess polyelectrolyte solution that is opposite to the polarity of its surface charge. In the process, a layer of oppositely charged polyelectrolyte layer is adsorbed on the surface of colloidal particles by electrostatic mutual attraction; excess polyelectrolyte is removed by centrifugation and washing. Then another polyelectrolyte solution or inorganic nanoparticle sol with opposite charge is selected , repeat the above process to make polyelectrolyte or inorganic nanoparticles adsorb alternately on the surface of the colloidal particles to form a multilayer film. The core-shell structure particles prepared by the LbL method can be obtained by dissolving or burning the core to remove the core. Capsules with nanometer or micron-diameter cavities. For example, the international patent (WO99 / 47252) uses negatively charged polystyrene sulfonate sodium (PSS) and positively charged polystyrene amine (PAH) in melamine formaldehyde microspheres (MF). Multi-layer coating, and finally use hydrogen fluoride to remove MF to obtain hollow polymer capsules; the disadvantage of the above patents is that MF templates need to be removed by strong acid to obtain hollow capsules, and the steps are cumbersome; Integrity, size, permeability, surface morphology and elasticity have a great influence, and often cause the rupture of the capsule. In addition, the subsequent drug load is usually obtained through the penetration of the capsule wall, and the drug loading rate is low.

[0008] For fat-soluble drugs, there are two ways to prepare drug-loaded capsules by the LBL method, one is to dissolve the drug in a water-organic solvent mixed solution, then evaporate the organic solvent, and then the drug passes through the concentration gradient difference between the inside and outside of the capsule wall, Precipitate into the capsule to complete drug loading. The disadvantage of this method is that a large amount of organic solvents and non-biodegradable surfactants are used in the preparation of drug-loaded capsules

The second is to use fat-soluble drug crystals as templates to complete the microencapsulation of drugs through layer-by-layer self-assembly. The disadvantage is that organic solvents are still needed to dissolve the drug crystals.

Although the obtained capsules have good biocompatibility, the disadvantage is that the particle size of the magnetic microcapsules prepared by this method is in the micron order (>100 μm), which is difficult to apply to blood administration in vivo.

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