Introduction to Medicinal Chemistry: Synthesis and Investigation of Cross-Linked Alginate Beads with Embedded Micelles as Model Carriers of Hydrophobic Drugs

Polymer-based carriers of drugs are very promising and widely developed pharmaceutical formulations especially for delivery of hydrophobic drugs. They may provide protection of sensitive drug molecules on their way through a digestive system to the site of action as well as enable controlled release at desired pH conditions. Fabrications of such carriers followed by visualization and investigation of the release process are a perfect activity to introduce students to the problems of medical chemistry. They can be used with upper secondary school students (K10–12) as well as part of introductory chemistry university courses. The presented activity includes preparation of polymer-based beads containing micelles with encapsulated model hydrophobic dye (Nile red) using simple and safe ingredients. It is then followed by the observation of the release of the model dye from those water dispersible alginate beads at various pH values corresponding to the stomach and intestine conditions. These experiments are visual demonstrations of formations of drug-delivery systems and their actions at conditions mimicking the real biological systems, highlighting the importance of carriers in oral delivery of drugs.