Dissolution Rate Studies from a Stationary Disk/Rotating Fluid System
- 1 January 1988
- journal article
- Published by Springer Science and Business Media LLC in Pharmaceutical Research
- Vol. 5 (8), 495-500
- https://doi.org/10.1023/a:1015965223891
Abstract
The dissolution rates for hydrocortisone alcohol and acetate were determined using a stationary disk/ rotating fluid system. The hydrocortisone was compressed in a tablet die, and the die placed in a vessel above a rotating magnetic bar. Dissolution rates were evaluated in aqueous media under conditions involving the following independent variables: solubility (Cs), diffusion coefficient (D), viscosity (v), rotational speed (ω), and tablet radius (r). A design equation which relates dissolution rate (R) to these variables was formulated for the system R α CsD2/3(v) −1/6(ω) 1/2( r)3/2 This design equation adequately represents the system, which is related to fluid mechanics and convective diffusion models. The fluid mechanics model assumes that the fluid ideally rotates as solid-body rotation and the momentum layer is initiated at the outside radius of the tablet die. The convective diffusion model is based on the formation of a diffusion layer at the outside radius of the dissolving surface and a predictable relationship between the momentum and the mass transport quantities of bulk viscosity and diffusion coefficient. This configuration, like the rotating disk in a stationary fluid, offers the attractive attribute of being useful to study drug release mechanisms for systems of pharmaceutical interest.Keywords
This publication has 9 references indexed in Scilit:
- Mass transport in dissolution kinetics I: Convective diffusion to assess the role of fluid viscosity under forced flow conditionsJournal of Pharmaceutical Sciences, 1987
- Evaluation of a Tube Method for Determining Diffusion Coefficients for Sparingly Soluble DrugsJournal of Pharmaceutical Sciences, 1986
- Convective Diffusion Model for a Transport-Controlled Dissolution Rate ProcessJournal of Pharmaceutical Sciences, 1975
- Design and Evaluation of a Rotating Filter—Stationary Basket In Vitro Dissolution Test Apparatus I: Fixed Fluid Volume SystemJournal of Pharmaceutical Sciences, 1973
- Effect of Various Parameters Upon Diffusion-Controlled Dissolution of Benzoic AcidJournal of Pharmaceutical Sciences, 1972
- Solubility of Parabens in AlcoholsJournal of Pharmaceutical Sciences, 1969
- Solubility or Some Steroids in WaterJournal of Pharmaceutical Sciences, 1966
- Improved Holder for Intrinsic Dissolution Rate StudiesJournal of Pharmaceutical Sciences, 1965
- Determination of Solubility of a Metastable PolymorphJournal of Pharmaceutical Sciences, 1964