The effect of the dipalmitoylphosphatidylcholine lipid bilayer state on the adsorption of phenyltins

✍ Scribed by Marek Langner; Janina Gabrielska; Stanislaw Przestalski

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 88 KB
• Volume: 14
• Category: Article
• ISSN: 0268-2605
• DOI: 10.1002/(sici)1099-0739(200003)14:3<152::aid-aoc978>3.0.co;2-y

✦ Synopsis

The nonspecific adsorption of amphiphilic molecules onto the membrane depends both on the properties of the adsorbate and the state of the lipid bilayer. Electrostatic interactions drive the adsorption of charged molecules and hydrophobicity determines partition of the adsorbate into the membrane, whereas the steric compatibility of the lipid bilayer and the amphiphilic molecule is an additional factor to be accounted for when considering interaction between the adsorbate and the membrane. The adsorption of phenyltins was evaluated from changes in Fluorescein-PE fluorescence intensity. The pH sensitivity of fluorophore, located at the membrane surface, was utilized to detect charges introduced onto the membrane by adsorbing compounds. It has been shown that the state of the membrane affects phenyltin adsorption in accordance with the number of phenyl rings on the molecule. Furthermore, the membrane surface topology determines interfacially located triphenyltin adsorption, with a much weaker effect on deeply embedded diphenyltin. When the dipalmitoylphosphatidylcholine (DPPC) model membrane is in the ripple phase, with complex surface morphology, phenyltin adsorption is greatly enhanced. Results presented in this paper show that steric constraints imposed on rigid and bulky amphiphilic compounds by ordered alkyl chains and membrane surface topology affect nonspecific molecule adsorption onto the membrane.