Novel preparation method of liposome

Abstract

The invention provides a novel preparation method of liposome, aiming at solving the defect in the process that the liposome is prepared by the medicine which is easy to oxidize, hydrolyze and denature, wherein the liposome is higher in encapsulation ratios to various medicines. The preparation method of the liposome comprises the following steps of: a. dissolving a lipidic substance and a lipophilic substance which form into the liposome into an organic solvent to form into an oil phase solution (O); b. dissolving a water-soluble substance to be encapsulated into water to form into a water phase solution (W); c. mixing and emulsifying the two solutions according to a proper proration to obtain a W/O type emulsion (comprising micro emulsion and reversed micelle); d. drying the obtained W/O type emulsion in a freezing way to remove a solvent so as to obtain a freeze-dried product; and e. hydrating the obtained freeze-dried product to obtain the liposome. The novel preparation method is simple in technical process and easy to implement.

Description

technical field [0001] The invention relates to the technical field of biomedicine, in particular to a new method for preparing liposomes (including liposomes, niosomes). Background technique [0002] Liposomes are closed vesicle-like structures formed by phospholipid bilayers. Liposomes can be divided into unilamellar yesicles, multilamellar yesicles and multivesicular liposomes according to their structure. Liposomes were first discovered in 1965 by British Alec D.Bangham. Since then, it has been found that liposomes have great application value as material carriers, especially drug carriers, so liposomes have been systematically and extensively studied. [0003] After more than 20 years of exploration, researchers have proposed many valuable liposome preparation methods. At present, liposomes are mainly prepared by dispersion technique, which can be divided into three categories: 1) Based on mechanical dispersion technique. Such as the film dispersion method (film dis...

AI Technical Summary

Problems solved by technology

[0007] (2) Phospholipids are usually prone to hydrolysis and oxidation when they exist in the water phase

Since phospholipids are hydrolyzed to form lysophospholipids, on the one hand, the toxicity of the preparation is increased, and on the other hand, liposomes are easily disintegrated, resulting in leakage of the encapsulated drug.

[0008] (3) Liposomes are suspended in the water phase. During storage, the drug may leak, resulting in a change in the encapsulation rate of the drug, thereby affecting the efficacy of the preparation

If the drug itself is easily hydrolyzed, the stability problem of the formulation is more prominent

[0009] 2. Encapsulation rate problem

However, both the pH gradient and the ammonium sulfate gradient active drug loading method need to provide a large difference in pH environment inside and outside the liposome membrane, which is not only not suitable for drugs that are sensitive to acid and alkali, but also easily causes phospholipid decomposition and denaturation.

In addition, the active drug loading method is only suitable for dissociable drugs, and its application range is relatively limited

[0010] 3. Sterilization of liposome preparations

This may not be possible with some liposome preparation processes

[0011] 4. Particle size control of liposomes

This in turn often leads to further leakage of the drug, affecting the quality of the formulation

[0014] 5. Drug release problems

[0015] Some drugs (such as topotecan and other camptothecin drugs) are released too quickly after being encapsulated into liposomes, and the focus concentration of the drugs cannot be achieved; while some drugs (such as platinum preparations) are released too quickly after being encapsulated into liposomes. Slow, after the liposome reaches the lesion site, it cannot reach the effective therapeutic concentration due to the slow release of the drug