title: Molecular interactions between DPPC and morphine derivatives: a DSC and EPR study.
abstract: The interaction between different morphine derivatives (morphine, codeine, N-methyl-morphine, N-methyl-codeine) and alpha-L-dipalmitoyl phosphatidylcholine (DPPC) liposomes was studied with differential scanning calorimetry (DSC) and electron paramagnetic resonance (EPR) spectroscopy. Small unilamellar DPPC-liposomes with the given morphine-derivative were prepared by sonication. The size distribution of liposomes was checked by dynamic light scattering (DLS). The amount of entrapped morphine was determined spectrophotometrically. Our results indicate that the morphine and its derivatives principally interact with the lipid head groups, and this interaction leads to a decrease in the mobility of the polar head groups, especially in case of codeine and N-methyl-codeine.
authors.affiliation: Faculty of Medicine, Institute of Biophysics and Radiation Biology, Semmelweis University, Budapest VIII. Puskin u. 9, P.O. Box 263, H-1444 Budapest, Hungary.
authors.forename: M
authors.initials: M
authors.lastname: Budai
authors.forename: Zs
authors.initials: Z
authors.lastname: Szabó
authors.forename: M
authors.initials: M
authors.lastname: Szogyi
authors.forename: Pál
authors.initials: P
authors.lastname: Gróf
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000008:administration & dosage / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D003061:Codeine / Q000008:administration & dosage / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D008081:Liposomes; D008560:Membrane Fluidity; D009020:Morphine / Q000008:administration & dosage / Q000737:chemistry*; D012399:Rotation
chemical_list: D008081:Liposomes; D015060:1,2-Dipalmitoylphosphatidylcholine; D009020:Morphine; D003061:Codeine