Another object of this invention is to propose a process for preparing poly DL-lactide-co-glycolide nanoparticles having streptomycin encapsulated therein.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a process for a process for the preparation of Poly DL-lactide-co-glycolide nanoparticles having streptomycin encapsulated therein comprising the steps of:
i) preparation of a polymer solution in an organic solvent and
drug solution in water, wherein the ratio of said drug and polymer is 1:1 w/w,
ii) mixing the aqueous solutions of steps (i) with the organic solution in a ratio of 1:5-20 volume by volume followed by sonication for 45-120 sec at 4-15°C to obtain a primary emulsion,
iii) adding the above emulsion to aqueous PVA and resonicating for 2-5 minutes at 4-15°C, which is subjected to stirring for 18-30 hr. under cold conditions,
iv) stirring the emulsion and centrifuging at 8000-12000 rpm for 15-30 minutes at 4-20°C to obtain pellet,
v) washing the said pellets 3-4 times with DW/NS/PBS, reconstituting the same and lyophilizing.

WE CLAIM:
1. A process for the preparation of Poly DL-lactide-co-glycolide nanoparticles
having streptomycin encapsulated therein comprising the steps of:
i) preparation of a polymer solution in an organic solvent and solution of Streptomycin in water, characterized by the ratio of said Streptomycin and polymer is 1:1 w/w,
ii) mixing the aqueous solutions of steps (i) with the organic solution in a ratio of 1:5-20 volume by volume followed by sonication for 45-120 sec at 4-15°C to obtain a primary emulsion,
iii) adding the above emulsion to aqueous PVA and resonicating for 2-5 minutes at 4-15°C, which is subjected to stirring for 18-30 hr. under cold conditions,
iv) stirring the emulsion and centrifuging at 8000-12000 rpm for 15-30 minutes at 4-20°C to obtain pellet,
v) washing the said pellets 3-4 times with DW/NS/PBS, reconstituting the same and lyophilizing.
2. A process as claimed in claim 1, wherein the solution of polymer such as
PLG is prepared in an organic solvent preferably dichloromethane (DCM) in the ratio of 1:0.3-1 weight by volume to obtain an organic solution.
3. A process as claimed in claim 1, wherein the solution of Streptomycin such
as hydrophilic Streptomycin is prepared in DW/NS/PBS in a ratio of 1:0.1-
100 weight by volume to obtain an aqueous solution.
4. A process as claimed in any of the preceding claims, wherein the primary emulsion is poured into 0.8-2.5% PVA solution keeping DCM: PVA ratio at 1:0.5-1.5.