Acetone → Hydroxyacetic acid--2-hydroxypropanoic acid (1/1)

Temperature

40 °C

PLGA (PLGA7520, lactic acid/glycolic acid=75/25, weight average molecular weight 20,000, manufactured by Wako Pure Chemical Industries, Ltd.) (2 g) was dissolved in acetone (20 mL), and pioglitazone hydrochloride (100 mg) dissolved in methanol (10 mL) was added to give a polymer solution. The solution was added dropwise at a constant rate of 4 mL/min to an aqueous solution (50 mL) of 2 wt % polyvinyl alcohol (PVA, manufactured by KURARAY CO., LTD.) with stirring at 40° C. At this time, an emulsion droplet of a nanometer size is prepared due to a self-emulsion action caused by the turbulence in the emulsion droplet surface by mutual diffusion of acetone, methanol and water. Thereafter, acetone and methanol were evaporated and the obtained PLGA nanoparticle suspension was centrifuged (centrifuge acceleration 41000 G, −20° C., 20 min) to give PLGA nanoparticle precipitate, which was resuspended in purified water to remove excess PVA not adsorbed on the PLGA surface. Thereto was added an aqueous solution (50 mL) of 0.02 wt % chitosan (manufactured by Katakura Chikkarin Co., Ltd.), and the mixture was stirred for 1 hr and freeze-dried at −45° C. to powderize pioglitazone-containing chitosan-modified PLGA nanoparticles.

1. additionwas added
2. customto give a polymer solution
3. customAt this time, an emulsion droplet of a nanometer size is prepared due to a self-emulsion action
4. customThereafter, acetone and methanol were evaporated
5. custom(centrifuge acceleration 41000 G, −20° C., 20 min)

ORD record

ord-53d2df571b28493586399d2fafcce680

Source dataset

uspto-grants-2012_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08337896B2