SODIUM ALGINATES AS DILUENTS IN HARD GELATIN CAPSULES CONTAINING IBUPROFEN AS A MODEL-DRUG

The object of the study reported here was to investigate the effects o f 14 grades of sodium alginate (Manugels(R) and Manucols(R)) on the di ssolution of ibuprofen from hard gelatin capsules. Three drug: additiv e ratios were investigated. Dissolution rates of each formulation foll owed zero-order kinetics. The rate constants varied in the Manugel ser ies from 5.8 to 19.4% . h-1 and in the Manucol series from 8.0 to 58.8 % . h-1. As a rule, the higher the viscosity grade of sodium alginate the lower the rate of release of ibuprofen. However, rank order correl ation was not perfect. Particle size also seemed to have some effect: bigger particles gave less permeable gels.