Technical guides, an interactive dissolution simulator, and reference material to help you specify the right geometry for your application - before you place an order.
Adjust diameter, thickness, and compound properties to predict how quickly a pressed tablet dissolves in solution. The model uses the validated Noyes-Whitney equation with Hixson-Crowell shrinking-surface geometry and full sink correction.
Benchmarked against benzoic acid in water at 25°C. Accurate within 4% of literature IDR values under equivalent diffusion layer conditions.
Short, practical references written for scientists - not engineers. Each covers one decision point in the mold specification process.
Why surface area to volume ratio is the single most predictive geometric parameter for dissolution rate, and how to calculate it for cylinders, spheres, discs, and domes.
Request PDFA decision framework for mold material selection based on compound chemistry, casting temperature, solvent contact, regulatory requirements, and production volume.
Request PDFWorked examples showing the relationship between cavity volume tolerance and unit-to-unit mass variance - critical for potent compounds and limited-supply intermediates.
Request PDFComparative dissolution profiles for the five core geometries. Includes the governing equations and practical guidelines for matching form factor to target T₅₀ and T₈₀ release windows.
Request PDFA walkthrough of the information required for a DFM review - from CAD formats and dimensional callouts to compound class, casting method, and downstream process constraints.
Request PDFWe write technical reference material on request. If there's a form factor question your team keeps running into, let us know.
Request a Guide →Definitions written for scientists who work with compounds - not for pharmacokineticists. Focused on what the terms mean for mold geometry decisions.
The governing equation for dissolution rate. States that the rate of mass transfer from a solid surface into solution is proportional to the surface area and the concentration gradient at the surface.
The dissolution rate per unit surface area under sink conditions. A compound property (not a tablet property) - independent of geometry. Used to compare inherent solubility kinetics between compounds.
Describes how surface area decreases as a tablet erodes, using the cube-root relationship between mass and surface area. Applies when the tablet dissolves uniformly from all faces while maintaining its aspect ratio.
The thin stagnant film of solvent adjacent to the dissolving surface through which the compound must diffuse before entering the bulk. Agitation reduces h_d and accelerates dissolution. Typically 10–100 µm under experimental conditions.
A dissolution experiment is under "sink conditions" when the dissolved concentration in the vessel remains much lower than the saturation solubility - typically C < 0.2 × Cs. Ensures a near-constant driving gradient and prevents premature plateau.
Surface area divided by volume. The most important geometric predictor of dissolution rate - higher SA/V means faster dissolution for the same compound. Thinner tablets and smaller diameters both increase SA/V.
The time to 50%, 80%, or 90% dissolution of the initial tablet mass. T₈₀ is a common regulatory and formulation benchmark. T₉₀ marks near-complete dissolution. These are outputs of geometry and compound properties - not design inputs.
The diffusion coefficient of the compound in the solvent - a measure of how quickly molecules spread through the medium. Depends on molecular size, solvent viscosity, and temperature. For small molecules in water at 25°C, typically 0.5–2.0 × 10⁻⁹ m²/s.
Our engineers respond to technical inquiries within 4 business hours.