Center for Electrochemistry, Department of Chemistry and Biochemistry, University of Texas at Austin, 1 University Station, A5300, Austin, TX 78712-0165, USA.
Proc Natl Acad Sci U S A. 2010 Sep 28;107(39):16783-7. doi: 10.1073/pnas.1011614107. Epub 2010 Sep 13.
Changes in HeLa cell morphology, membrane permeability, and viability caused by the presence of Triton X-100 (TX100), a nonionic surfactant, were studied by scanning electrochemical microscopy (SECM). No change in membrane permeability was found at concentrations of 0.15 mM or lower during an experimental period of 30 to 60 min. Permeability of the cell membrane to the otherwise impermeable, highly charged hydrophilic molecule ferrocyanide was seen starting at concentrations of TX100 of about 0.17 mM. This concentration level of TX100 did not affect cell viability. Based on a simulation model, the membrane permeability for ferrocyanide molecules passing though the live cell membrane was 6.5 ± 2.0 × 10(-6) m/s. Cells underwent irreversible permeabilization of the membrane and structural collapse when the TX100 concentration reached the critical micelle concentration (CMC), in the range of 0.19 to 0.20 mM. The impermeability of ferrocyanide molecules in the absence of surfactant was also used to determine the height and diameter of a single living cell with the aid of the approach curve and probe scan methods in SECM.
通过扫描电化学显微镜（SECM）研究了非离子表面活性剂 Triton X-100（TX100）存在时 HeLa 细胞形态、膜通透性和活力的变化。在 30 至 60 分钟的实验期间，当浓度为 0.15 mM 或更低时，未发现膜通透性发生变化。当 TX100 的浓度约为 0.17 mM 时，开始看到细胞膜对不可渗透的、带高电荷的亲水分子亚铁氰化物具有通透性。该浓度水平的 TX100 不会影响细胞活力。基于模拟模型，穿过活细胞膜的亚铁氰化物分子的膜通透性为 6.5 ± 2.0×10(-6) m/s。当 TX100 浓度达到临界胶束浓度（CMC）时，细胞的膜通透性会发生不可逆的破坏，结构崩溃，CMC 的范围在 0.19 至 0.20 mM 之间。在没有表面活性剂的情况下，亚铁氰化物分子的不可渗透性也被用来确定单个活细胞的高度和直径，借助于 SECM 的接近曲线和探针扫描方法。
