Dissolution Testing — Method Development, Apparatus & Discrimination
Dissolution testing measures how a solid dosage form releases its active under defined conditions. A useful method is both discriminating — sensitive to meaningful formulation or process changes — and reproducible; compendial conditions are a starting point, not always the final method.
Choose apparatus and conditions deliberately
Basket, paddle, flow-through and other apparatus suit different dosage forms. Medium composition, volume, degassing, agitation and temperature all affect the profile; document the rationale for each. For modified-release products, the method must reflect the release mechanism across the full profile, not a single time point.
Demonstrate discrimination and robustness
A method that cannot distinguish a changed formulation gives false assurance. Ask the laboratory how discrimination was assessed and how the method handles sink conditions, coning, adsorption to filters and autosampler variability. Validation follows ICH Q2 principles with dissolution-specific considerations.
Connect dissolution to the decision
Quality control release, bioequivalence-supporting profiles, method transfer and stability time points each impose different requirements. State which purpose applies and whether a compendial monograph method must be verified or a new method developed. FDA maintains a dissolution methods database that is a useful reference for many products.
Sample considerations
- Provide the dosage form, strength, formulation details and any existing method or monograph.
- State the purpose: QC release, development, comparison profiles or stability.
- Agree apparatus, media, sampling plan, validation scope and reporting format.
Questions to ask a laboratory
- Why are the chosen apparatus and conditions appropriate for this product?
- How was method discrimination demonstrated?
- Does the work support QC release, development comparison, or both?
Laboratories with relevant capabilities
- Scout Scientific (Greenville, NC) — Dissolution testing
Sources and scope references
FDA — dissolution methods database
Related testing briefs
Confirm standard edition, jurisdiction and actual laboratory scope. Service references are not partnerships or endorsements.