Medical College of Wisconsin
CTSICores SearchResearch InformaticsREDCap

Partitioning and localization of spin-labeled amantadine in lipid bilayers: an EPR study. J Pharm Sci 1998 Oct;87(10):1249-54



Pubmed ID





EPR was used to study the distribution of the spin-labeled amantadine (AA-SL) between the bulk hydrophobic-hydrocarbon solvent, light paraffin oil, and water and between hydrophobic-hydrocarbon chain region of lipid membranes and water. The AA-SL molecules were soluble in both hydrophobic and polar regions of investigated systems. It was shown that the partition coefficient of AA-SL between the hydrocarbon region of the L-alpha-dimyristoylphosphatidylcholine fluid-phase membrane and water is much higher than between bulk hydrocarbon solvent and water. Furthermore, the partitioning of AA-SL into membranes of multilamellar liposomes made of L-alpha-dimyristoylphosphatidylcholine, L-alpha-dipalmitoylphosphatidylcholine, and L-alpha-distearoylphosphatidylcholine was studied as a function of temperature, indicating no abrupt change at the main phase transition of these membranes. It is also clear from our data that AA-SL can penetrate into the gel-phase membrane practically with the same partitioning as into the fluid-phase membrane. Furthermore, it was shown that at least part of the AA-SL molecule is deeply buried in the hydrocarbon chain region of the membrane.

Author List

Subczynski WK, Wojas J, Pezeshk V, Pezeshk A


Witold K. Subczynski PhD Professor in the Biophysics department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Antiviral Agents
Electron Spin Resonance Spectroscopy
Lipid Bilayers
Spin Labels