Abstract:

Starch was firstly acylated by acetic anhydride, fluorescein isothiocyanate(FITC) was then covalently attached onto the starch acetate. And the fluorescein-labeled starch acetate could self-assemble to form uniform nanospheres encapsulated with ibuprofen. The controlled-release properties of obtained ibuprofen-loaded fluorescein-labeled starch nanospheres were investigated in details. The amounts of drug-loading and release rate could be tuned by changing the amounts of fluorescein-labeled starch acetate, ibuprofen and volume ratio of acetone to water. The results showed that up to 69.5% of the drug could be encapsulated when the amounts of fluorescein-labeled starch acetate and ibuprofen were 200 mg and 60 mg, and the volumes of water and acetone were 50 mL and 20 mL, respectively. The drug release rate in vitro of these nanospheres was 62.7% at 48 h. Moreover, the release process in vitro of the drug-loaded nanospheres was characterized by scanning electron microscope(SEM) and confocal laser scanning microscope(CLSM).

Key words: starch nanosphere, fluorescein, ibuprofen, encapsulation efficiency, drug release