ISSN:
1573-904X
Keywords:
microencapsulation
;
cellulose acetate phthalate
;
enteric-coated granules
;
drug release in vitro
;
sulfamethoxazole
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract A formulation containing cellulose acetate phthalate for preparing enteric-coated granules was developed with the use of granulation and microencapsulation techniques. Drug release from tablets or tabletted microcapsules was measured in a disintegration apparatus and an in vitro variable-pH release simulator of the flow type. The release mechanism for the tablets or tabletted microcapsules was determined with the Higuchi matrix model, a first-order kinetic model, and the Weibull distribution function. Adding acetone directly to the mixture of sulfamethoxazole and cellulose acetate phthalate resulted in enteric-coated granules with more prolonged release than other granulation methods. Microencapsulation of the granules significantly delayed the drug release and enhanced the effectiveness of the enteric coating. Microencapsulated granules show release patterns that are sustained and can be simulated with three different release models, i.e., with square-root time plotting, diffusional first-order plotting, and Weibull distribution plotting. The enteric-coating behavior of the tablets was more clearly demonstrated with the variable-pH release simulator than with a fixed-pH dissolution method.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1016442330193
