Hybrid QM/MM Molecular Dynamics Study of Benzocaine in a Membrane Environment: How Does a Quantum Mechanical Treatment of Both Anesthetic and Lipids Affect Their Interaction.

Biomolecular dynamics studies using a QM/MM approach have been largely used especially to study enzymatic reactions. However, to the best of our knowledge, the very same approach has not been used to study the water/membrane interface using a quantum mechanical treatment for the lipids. Since a plethora of biochemical processes take place in this region, we believe that it is of primary importance to understand, at the level of molecular orbitals, the behavior of a drug in such an odd environment. In this work, we take advantage of an integration of the CPMD and the GROMACS code, using the Car-Parrinello method, to treat the benzocaine local anesthetic as well as two of the membrane lipids and the GROMOS force field to treat the remaining lipids and the water molecules.