STATISTICAL COMPARISON OF 2 METHODS OF DISSOLUTION OF SUSTAINED-RELEASE THEOPHYLLINE TABLETS

A comparative study of two methods of dissolution (Simoons Apparatus a nd USP XXII Apparatus II) has been accomplished using sustained-releas e 50 mg anhydrous theophylline tablets. Sovic(R) 374 MB, Eudragit(R) R L PM, Aquacoat(R) Methocel(R) K-15M, and Cutina(R) HR were some of the excipients used to elaborate inert, hydrophilic, and lipidic matrices . Theophylline release was prolonged in all cases, except when Aquacoa t was used as matrix constituent. Simoons device was found to be more accurate for inert matrix tablets, whereas USP apparatus was advantage ous for hydrophilic and lipidic matrix. ANOVA showed significant diffe rences among all the factors analyzed. The drug release kinetics was a djusted better to Higuchi's kinetic model than to the Noyes-Whitney or Weibull models from 10% to 70% release.