Development of Poly Lactic/Glycolic Acid (PLGA) Microspheres for Controlled Release of Rho-Associated Kinase Inhibitor

Figure 1

Characteristics of poly lactic/glycolic acid (PLGA) or poly lactic acid (PLA) microspheres for Y-27632 release. (a) PLGA microspheres were examined with a scanning electron microscope. The upper panel shows the surface of the microsphere, and the lower panel shows the internal structure of the microsphere. (b) PLGA or PLA microspheres were incubated in a PBS at 37°C for 14 days, and the amount of Y-27632 released was determined by HPLC. The effect of the molecular weight on the release profile for PLGA or PLA microspheres was evaluated. The cumulative amount of released Y-27632 was plotted in the graph (). (c) PLGA or PLA microspheres were incubated in PBS at 37°C, and the amount of Y-27632 released was determined by HPLC. The effect of the composition of lactic acid and glycolic acid on the release profile was evaluated (). The PLGA5005 release curve plotted is the same as that shown in Figure 1(b). (d) Y-27632 was dissolved in ultrapure water with or without gelatin, and PLGA5005 microspheres were prepared (). The incorporation rate was evaluated by HPLC. . (e) PLGA5005 with or without gelatin that incorporated Y-27632 was incubated at PBS at 37°C for 14 days, and the amount of Y-27632 released was determined by HPLC. Three independent experiments were performed.

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