title: Interactions of chlorpromazine with phospholipid monolayers: effects of the ionization state of the drug.
abstract: Molecular dynamics simulations have been performed to investigate the interactions between chlorpromazine (CPZ) and Langmuir monolayers of the zwitterionic dipalmitoylphosphatidylcholine (DPPC) and the anionic dipalmitoylphosphatidylglycerol (DPPG). Simulations for a fixed surface density and different charge states - neutral and protonated CPZ - were able to capture important features of the CPZ-phospholipid monolayer interaction. Neutral CPZ is predominantly found in the hydrophobic tail region, whereas protonated CPZ is located at the lipid-water interface. Specific interactions (hydrogen bonds) between protonated CPZ and the lipid head groups were found for both zwitterionic and anionic monolayers. We computed lipid tail order parameters and investigated the effects of the drug upon tail ordering. We also computed electrostatic surface potentials and found qualitative good agreement with experimental results.
authors.affiliation: Instituto de Química, Universidade Estadual de Campinas-UNICAMP, C.P. 6154 Campinas, SP, 13083-970, Brazil. monik@ifi.unicamp.br
authors.forename: Mónica
authors.initials: M
authors.lastname: Pickholz
authors.forename: Osvaldo N
authors.initials: ON
authors.lastname: Oliveira
authors.forename: Munir S
authors.initials: MS
authors.lastname: Skaf
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry; D002746:Chlorpromazine / Q000737:chemistry*; D003198:Computer Simulation; D006860:Hydrogen Bonding; D007477:Ions; D010715:Phosphatidylglycerols / Q000737:chemistry; D010743:Phospholipids / Q000737:chemistry*; D055672:Static Electricity
chemical_list: D007477:Ions; D010715:Phosphatidylglycerols; D010743:Phospholipids; D015060:1,2-Dipalmitoylphosphatidylcholine; D002746:Chlorpromazine; C030345:1,2-dipalmitoylphosphatidylglycerol