Abstract
The dissolution rates of two lots of hydrocortisone (fine and coarse) were simulated using a computer program based on a Noyes–Whitney-type equation. Derivations of the equation were made to compare the accuracy of simulations using spherical and cylindrical particle geometry, with and without a time-dependent diffusion layer thickness. To approximate better the shape of the hydrocortisone particles, a shape factor was used to relate cylindrical length to radius. The most accurate simulations were obtained by assuming cylindrical geometry with and without a time-dependent diffusion layer thickness for the fine and coarse hydrocortisone, respectively. The program was also modified to simulate initial particle size distributions based on the log normal probability density function.
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Lu, A.T.K., Frisella, M.E. & Johnson, K.C. Dissolution Modeling: Factors Affecting the Dissolution Rates of Polydisperse Powders. Pharm Res 10, 1308–1314 (1993). https://doi.org/10.1023/A:1018917729477
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DOI: https://doi.org/10.1023/A:1018917729477