Evaluation of the Interaction of Coumarins with Biomembrane Models Studied by Differential Scanning Calorimetry and Langmuir-Blodgett Techniques

Three coumarins, scopoletin (1), esculetin (2),and esculin (3), were investigated by differential scanningcalorimetry and LangmuirBlodgett techniques to gain informationabout the interaction of these compounds with cellularmembranes. Phospholipids assembled as multilamellar vesiclesor monolayers (at the airwater interface) were used as biomembrane models. Differential scanning calorimetry was employed tostudy the interaction of these coumarins with multilamellar vesicles and to evaluate their absorption by multilamellar vesicles. Theseexperiments indicated that 13 interact in this manner to different extents. The LangmuirBlodgett technique was used to studythe effect of these coumarins on the organization of phospholipids assembled as a monolayer. The data obtained were in agreementwith those obtained in the calorimetric experiments.