Anion binding to lipid bilayers: determination using fluorescent membrane probe by direct quenching or by competitive displacement approaches

详细信息    查看全文

• 作者：Kalinin ; Stanislav V. ; Molotkovsky ; Julian G.
• 关键词：Anions ; Lipid bilayers ; Fluorescent probes ; Quenching ; Binding parameters ; ApPC ; 1-acyl-2-[5-(9-anthryl)-4-pentenoyl]-sn-glycero-3-phosphocholine ; ApSM ; N-[5-(9-anthryl)-4-pentenoyl]sphingosine-1-phosphocholine ; BSM ; bovine brain sphingomyelin ; Chol ; chol
• 刊名：Journal of Biochemical and Biophysical Methods
• 出版年：2000
• 出版时间：November 20, 2000
• 年：2000
• 卷：46
• 期：1-2
• 页码：39-51
• 全文大小：223 K

文摘

An approach is described that enables anion binding to liposomal membranes to be assessed from the resulting quenching of fluorescent lipid probes included in the membranes. Lipid derivatives such as anthrylvinyl-labeled phosphatidylcholine (ApPC) and methyl 4-pyrenylbutyrate (MPB) were used because they bear nonpolar fluorophores that localize in the bilayer close to polar heads. Association constants (K_a) of iodide binding to bilayers of different composition were determined on the basis of direct quenching experiments. For anions that are non-quenchers or weak quenchers (thiocyanate, perchlorate and trichloroacetate), K_a values were obtained from the data of competitive displacement of iodide by these anions. This approach increases possibilities of fluorescence studies of ion-membrane interactions.