Relationship between planar and all-surface rate constants for drugs formulated in nondisintegrating cylindrical slow-release tablets.
The release of drug through the planar surface of a nondisintegrating tablet with an insoluble matrix has been described mathematically using the Higuchi release rate constant (kH). The release of drug through a similar all-surface tablet has been described by using a cubic equation and the all-surface rate constant (kr). Using sodium salicylate and quinidine sulfate as model drugs, the relationship between kH and kr was verified for cylindrical slow-release tablets. Accordingly, the rate constant obtained from a single exposed planar surface can be used to predict the rate constant (kr) when all surfaces of the tablet are exposed to dissolution fluid.
D003692:Delayed-Action Preparations; D007700:Kinetics; D008956:Models, Chemical; D011802:Quinidine; D012980:Sodium Salicylate; D012995:Solubility; D013607:Tablets
D003692:Delayed-Action Preparations; D013607:Tablets; D011802:Quinidine; D012980:Sodium Salicylate