Abstract
The drug release profiles of aspirin wax matrix tablet containing various amounts of sucrose and hard paraffin were measured in 0.1 M acetate buffer (pH 4.5) at 37°C. Bulk powders of aspirin and sucrose were mixed in hard paraffin melted at 110°C, and after cooling the wax matrix tablets (450 mg, 13 mm in diameter) were prepared by compression at 2000 kg/die. Since no tablet disintegrated during the dissolution test and the drug release profiles from the wax matrix were straight lines in a Higuchi plot, it is suggested that the drug release from this wax matrix system followed the Higuchi equation. This indicates that the drug diffusivity in the matrix pores determined the drug release rate. The drug release rates depended on the amount of sucrose; when the sucrose content increased, so did the drug release rate. The relation between the drug release rate and sucrose content were a straight line, indicating that the drug release rate was controlled by the porosity of the matrix.
