Effects of ions and detergents in drug partition chromatography on liposomes.
We have determined drug partitioning into phospholipid bilayers by immobilized-liposome chromatography (ILC). Electrostatic effects on the drug partitioning were observed on neutral bilayers at low ionic strength. The size of the counterions affected the partitioning. When liposomes were supplemented with ionic detergents the partitioning of charged drugs was strongly affected, allowing complete separation of drugs of different charges which showed similar retention on neutral bilayers. Partial separation was obtained on bilayers containing fatty acid. Detergent ions or fatty acid inserted into phospholipid bilayers affected the partitioning of drugs much more than did free ions or phospholipid head group charges.
Boija
Elisabet
E
Department of Biochemistry, Biomedical Center, Uppsala University, Box 576, SE-75123 Uppsala, Sweden. Elisabet.Boija@biokem.uu.se
Lundquist
Anna
A
Martínez Pla
Juan José
JJ
Engvall
Caroline
C
Lundahl
Per
P
D002853:Chromatography, Liquid / Q000379:methods*; D003902:Detergents; D005227:Fatty Acids / Q000737:chemistry; D008051:Lipid Bilayers; D008081:Liposomes; D009994:Osmolar Concentration; D004364:Pharmaceutical Preparations / Q000302:isolation & purification*; D010743:Phospholipids / Q000737:chemistry
D003902:Detergents; D005227:Fatty Acids; D008051:Lipid Bilayers; D008081:Liposomes; D004364:Pharmaceutical Preparations; D010743:Phospholipids