[Development of gentamicin sulfate sustained release tablet remaining-floating in stomach]

Gentamicin sulfate sustained-release tablet remaining-floating in stomach (G-HBS) was developed based on the hydrodynamically balanced system. The dissolution rate of G-HBS was determined by rotary basket method (100 r/min, 37 +/- 0.5 degrees C, 0.1 mol/L HCl). The release characteristics of G-HBS showed basically first order kinetics with the dissolution rate constant (Kr) of 0.3992 h-1. The mean dissolution time (MDT) of G-HBS was 2.53 h-1. The density of G-HBS was found to have no significant influence on dissolution of G-BHS. The gamma-scintiphoto technique was used to examine the gastric retention time of G-HBS and GCT (gentamicin sulfate conventional tablet). It was shown that the gastric retention time of all subjects taking G-HBS under fed and fasted conditions were all over 4 h, in contrast with GCT, only 1-2 h. The stability of G-HBS was investigated and a tentative two-year expiration date was established. Spectrophotometry for the determination of gentamicin was established. The effect of G-HBS on Campylobacter pyloridis-associated chronic gastritis was examined through clinical trials.