Lyophilization is a useful technique to avoid the release of the drug by the polymeric micelles in solution and it is also able in many cases to avoid a change in size of the particles.

Usually we lyophilize the samples for stability and storage. As you can not keep the micelles in solutions for long time (for storage), so it is better to freeze-dry. Then you can use the freshly prepared micelle solutions for release experiments or for any other required assay.

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