Miscibility and dispersability test

When developing a lipid-based formulation, solubility screening in individual excipients is the first step. If a single excipient cannot solubilize the entire therapeutic dose, a multi-excipient formulation is developed. The second step of the process enables to assess the miscibility of the binary mixtures of excipients and their dispersability in water.

Miscibility and dispersability testing: part of the LBF development

A systematic approach is recommended to develop lipid-based formulations:

  • Assessing the solubility of the drug in various excipients
  • Evaluate miscibility and dispersion of selected excipients for  ternary diagramming
  • In vitro lipolysis testing

For more information:

A Systematic Approach to Lipid-Based Formulation Development for a Poorly Soluble API, Fenofibrate
Masumi Dave, M.S., Jason Le Pree, Ph.D., R.Ph.

Miscibility testing

The miscibility test is a simple visual evaluation of binary combinations over a 24-hour period to ensure the mixture is stable and homogenous over time.

Example of miscible mixtures of lipid excipients (left)

Example of non-miscible mixtures of lipid excipients (right)

Dispersability testing

One gram of the lipid-based formulation is added to 200mL of water at 37°C. A visual inspection enables to determine if the combination of excipients is homogenous or not.

Example of dispersable mixtures of lipid excipients (left)

Example of non-dispersable mixtures of lipid excipients (right)