Drug – bio-affecting and body treating compositions – Preparations characterized by special physical form – Particulate form
Patent
1999-08-02
2000-11-21
Azpuru, Carlos A.
Drug, bio-affecting and body treating compositions
Preparations characterized by special physical form
Particulate form
264 432, 264 433, 264 46, 4284021, A61K 950, B01J 1302, B65B 1302, B29B 1302, B32B 516
Patent
active
061499447
DESCRIPTION:
BRIEF SUMMARY
This application is a 371 continuation of PCT/KR97/00055 filed Apr. 1, 1997, which is a continuation of KR19669755 filed Apr. 1, 1996.
FIELD OF THE INVENTION
The present invention relates to an improved preparation method for a biodegradable polymeric microspheres using a solvent extraction method and a preparation method for biodegradable polymeric microspheres for treating local inflammation disease, in particular, for treating sinusitis and middle ear inflammation.
DESCRIPTION OF RELATED ART
Esters, especially a single or combined polymeric esters consisting of a single molecule of a lactic acid and a glycolic acid have received much attention in the development of a sustained medicine delivery system due to their high biocompatibility, biodegradability and applicability for the human body as recognized for its stable usage as suture. Generally, they have been employed in the form of microspheres, transplantates, and fibers. Various microspheres preparation methods using a biodegradable polymeric ester have been reported. Among these, a solvent evaporation method is widely used. This method is directed to dissolving a polymer in a proper solvent and then dissolving or dispersing a therapeutic agent, which in turn, is dispersed in an aqueous phase containing a surface active agent. Thereafter, it is heated to evaporate the solvent of the polymer to obtain microspheres.
Since this method is useful for encapsulation of only hydrophobic medicine due to its characteristic preparation process, recently there has been developed a W/O/W type emulsion method which is directed to separately fabricating an aqueous phase containing a water soluble medical agent, then dispersing the same into an organic phase, whereby it is possible to enhance the encapsulation efficiency of the agent. In addition, there is disclosed a solvent diffusion method which is directed to adding a water-soluble solvent such as acetone to an organic solvent being a solvent of a polymer, in order to easily diffuse the organic solvent into an outer aqueous phase. Recently, a solvent extraction method has been developed to solidify a polymer by extracting an organic solvent with a non-solvent which cannot dissolve the polymer but is well mixed with the solvent of the polymer.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an improved preparation method for biodegradable polymeric microspheres using a solvent extraction method and a preparation method for biodegradable polymeric microspheres for treating local inflammation using the same which overcome the aforementioned problems encountered in the conventional art.
It is another object of the present invention to provide an improved preparation method for biodegradable polymeric microspheres using a solvent extraction method and a preparation method for microspheres for treating local inflammation using the same which are capable of more effectively preventing a decrease of an encapsulation efficiency of an agent compared to the conventional solvent extraction method.
It is another object of the present invention to provide an improved preparation method for biodegradable polymeric microspheres using a solvent extraction method and preparation method for microspheres for treating local inflammation using the same which are basically directed to developing a continuously releasing therapeutic agent in order to cure a local inflammative disease.
It is another object of the present invention to provide an improved preparation method for biodegradable polymeric microspheres using a solvent extraction method and preparation method for microspheres for treating a local inflammation disease using the same which are capable of effectively curing ozena such as sinusitis and a middle ear inflammation.
The preparation method for biodegradable polymeric microspheres according to the present invention includes a step for first preparing a W/O type emulsion by mixing an inner aqueous phase and an organic phase comprising an organic solvent of polymer in whi
REFERENCES:
patent: 5445832 (1995-08-01), Orsolini et al.
patent: 5478564 (1995-12-01), Wantier et al.
patent: 5753234 (1998-05-01), Lee et al.
Jeong Seo Young
Kim Yong-Hee
Kwon Ick Chan
Azpuru Carlos A.
Korea Institute of Science and Technology
LandOfFree
Preparation method for biodegradable polymeric microspheres usin does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Preparation method for biodegradable polymeric microspheres usin, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Preparation method for biodegradable polymeric microspheres usin will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1254425