| Abstract: | The penetration of tetracaine into monolayers of phosphatidylcholine and trioctanoin at different surface pressures, and the penetration of dibucaine, tetracaine, butacaine, lidocaine, and procaine into monolayers of didecanoylphosphatidylcholine at II = 10 mN/m was determined by the use of a modified Gibbs adsorption equation. These data were shown to fit a geometric model and compared favorably with data determined by a method based on the geometric model. The penetration of tetracaine into phosphatidylcholine monolayers was pressure dependent. At II = 10 mN/m, the local anesthetics penetrate into a phosphatidycholine monolayer in the order: dibucaine greater than tetracaine greater than butacaine greater than lidocaine greater than procaine. This correlates with their potencies in blocking nerve conduction and inhibiting phospholipase A2. |
