Studies on the influencing factors on the drug release from sodium alginate matrices

AimTo investigate the ^{in vitro} influencing factors on drug release from matrices with sodium alginate as the hydrophilic polymer. MethodsSodium alginate hydrophilic matrix tablets were prepared by direct compression method with theopylline as a model drug. The ^{in vitro} influencing factors on drug release behavior from matrices were studied by investigating the swelling, water uptake and erosion characteristics of pure sodium alginate matrices. ResultsThe results showed that drug release rate and drug release mechanism were both related to the viscosity of sodium alginate used in matrices, pH values and ionic strength of dissolution media and rotation speeds. ConclusionSodium alginate can be tailor-made to suit the demands of applicants in sustained delivery systems as a good candidate of hydrophilic polymer.