Burns Scott T, Agbodjan Armel A, Khaledi Morteza G
North Carolina State University, Department of Chemistry, Raleigh 27695-8204, USA.
J Chromatogr A. 2002 Oct 11;973(1-2):167-76. doi: 10.1016/s0021-9673(02)00955-x.
The nature of solute interactions with biomembrane-like liposomes, made of naturally occurring phospholipids and cholesterol, was characterized using electrokinetic chromatography (EKC). Liposomes were used as a pseudo-stationary phase in EKC that provided sites of interactions for uncharged solutes. The retention factors of uncharged solutes in liposome EKC are directly proportional to their liposome-water partition coefficients. Linear solvation energy relationship (LSER) models were developed to unravel the contributions from various types of interactions for solute partitioning into liposomes. Size and hydrogen bond acceptor strength of solutes are the main factors that determine partitioning into lipid bilayers. This falls within the general behavior of solute partitioning from an aqueous into organic phases such as octanol and micelles. However, there exist subtle differences in the solvation properties of liposomes as compared to those of octanol and various micellar pseudo-phases such as aggregates of sodium dodecyl sulfate (SDS), sodium cholate (SC), and tetradecylammonium bromide (TTAB). Among these phases, the SDS micelles are the least similar to the liposomes, while octanol, SC, and TTAB micelles exhibit closer solvation properties. Subsequently, higher correlations are observed between partitioning into liposomes and the latter three phases than that into SDS.
利用电动色谱法（EKC）对由天然存在的磷脂和胆固醇制成的类生物膜脂质体与溶质之间相互作用的性质进行了表征。脂质体在EKC中用作假固定相，为不带电溶质提供相互作用位点。脂质体EKC中不带电溶质的保留因子与其脂质体-水分配系数成正比。建立了线性溶剂化能关系（LSER）模型，以揭示各种类型相互作用对溶质分配到脂质体中的贡献。溶质的大小和氢键受体强度是决定其分配到脂质双层中的主要因素。这符合溶质从水相分配到有机相（如辛醇和胶束）中的一般行为。然而，与辛醇和各种胶束假相（如十二烷基硫酸钠（SDS）、胆酸钠（SC）和十四烷基溴化铵（TTAB）的聚集体）相比，脂质体的溶剂化性质存在细微差异。在这些相中，SDS胶束与脂质体最不相似，而辛醇、SC和TTAB胶束表现出更接近的溶剂化性质。随后，观察到溶质分配到脂质体与后三个相之间的相关性高于分配到SDS中的相关性。
