EFFECTS OF POLY(VINYLPYRROLIDONE) AND ETHYLCELLULOSE ON ALGINATE MICROSPHERES PREPARED BY EMULSIFICATION

Authors
Citation
Lw. Chan et Pws. Heng, EFFECTS OF POLY(VINYLPYRROLIDONE) AND ETHYLCELLULOSE ON ALGINATE MICROSPHERES PREPARED BY EMULSIFICATION, Journal of microencapsulation, 15(4), 1998, pp. 409-420
Citations number
22
Categorie Soggetti
Pharmacology & Pharmacy","Chemistry Applied","Engineering, Chemical
ISSN journal
02652048
Volume
15
Issue
4
Year of publication
1998
Pages
409 - 420
Database
ISI
SICI code
0265-2048(1998)15:4<409:EOPAEO>2.0.ZU;2-W
Abstract
Calcium alginate microspheres were prepared by an emulsification proce ss. The effects of two co-polymers, namely poly(vinylpyrrolidone) and ethylcellulose, on the properties of the microspheres were studied. Mi crospheres prepared with and without poly(vinylpyrrolidone) were spher ical and discrete. The microspheres containing poly(vinylpyrrolidone) exhibited a better flow property but the drug content was lower and th e drug release rate higher. The method of incorporating poly(vinylpyrr olidone) was found to (significantly) affect the size distribution and drug content of the microspheres. Ethylcellulose produced marked aggr egation of the microspheres which also showed a lower drug content, bu t a slower drug release. The retardation in drug release was attribute d to the formation of aggregated microspheres with a less permeable ma trix. The addition of triethyl citrate, which is a water-soluble plast icizer, was found to increase the rate of drug release while the use o f a higher viscosity grade of ethylcellulose produced the opposite eff ect. Ethylcellulose improved the flowability of the microspheres to a greater extent than poly(vinylpyrrolidone).