表面活性剂单体引起的细胞膜失稳

表面活性剂常用于细胞裂解、脂质体外排与膜组分搜集等.但在临界成胶束浓度以下,它如何以单体状态与生物膜作用的机制与调控仍存在很多疑问.本文研究了表面活性剂带电性对膜失稳的影响.石英电子微天平检测发现非离子型Triton X-100产生了最显著的磷脂膜结构三维再组装.荧光显微观测表明膜表面生成了非稳的出芽微泡,在机械扰动下可发生解离.该表面活性剂溶液环境中的体外细胞也出现了活力丧失.但是,离子型CTAB与SDS却无法触发相似的膜失稳与细胞失活效应.分析认为,由于不存在后两者体系中的单体间静电排斥, Triton X-100更易高效地插入生物膜,从而诱导膜结构再组装.研究深化了表面活性剂与生物膜作用机制的理解,对表面活性剂在生物医药、膜组分萃取等领域的深化应用提供了指导与帮助.

Cell Membrane Instability Caused by Detergent Monomers

Detergents are commonly used in cell lysis, lipid extraction, and membrane component collection. However, there are many questions remained about the mechanism and regulations of the interactions between biomembranes and detergents in monomer state, where the critical micelle concentration was not reached. In this paper, the effects of the charge of detergent monomers on membrane instability have been studied comprehensively. In quartz crystal microbalance with dissipation monitor measurements, the most significant three-dimensional reassembly of phospholipid membrane was found in the biomembrane interaction with the non-ionic Triton X-100 monomers. Fluorescence microscope images showed the formation of budding microbubbles, which is unstable and may be dissociated with the original membrane under mechanical disturbance in buffer rinsing. Hela cells lost viability in this Triton X-100 medium as well. However, the cationic CTAB and anionic SDS monomers could not induce similar effects on model membranes and Hela cells below the critical micelle concentrations. Their influences on biomembranes are generally weak and do not affect the membrane integrity. It is inferred that Triton X-100 could be inserted more efficiently into the biomembranes because of the absence of the intermolecular electrostatic repulsion, which exists in CTAB and SDS systems. The research deepens the understanding of the interaction mechanism between detergents and biomembranes. It provides guidelines and references for the further applications of detergents in biomedicines, membrane component extractions and other fields.