An NH₄Cl-superfused system for a cell-cultured pH-sensing transistor was developed for detecting ion leakage across the plasma membranes of model HepG2 cells. The screening of chemical species by the method developed and conventional membrane-leakage assays identified the types of membrane injuries: structural membrane disruption and pore formation. Apoptosis-mediated membrane disordering was detected by continuously monitoring the ion-barrier breakdown of the membranes using the transistor system for an extended period. Comparisons of the ISFET assay with conventional cytotoxicity assays distinguished the cell death by direct membrane injury from that by other organelle damage. Our cell-based transistor system is fast and sensitive to ion leakage of the plasma membrane due to the small hydrodynamic size of the proton and ammonium ions as the indicators. The combination of the ion leakage assay with the existing cytotoxicity assays is a new way of classifying membrane injury and cell death induced by external chemical stimuli.

中文翻译：

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使用基于全细胞的质子敏感场效应晶体管系统识别膜损伤和细胞死亡的类型

NH ₄开发了用于细胞培养的pH感测晶体管的Cl超融合系统，用于检测模型HepG2细胞质膜上的离子泄漏。通过开发的方法和常规的膜泄漏测定法对化学物质进行筛选，从而确定了膜损伤的类型：结构性膜破裂和孔形成。通过长时间使用晶体管系统连续监测膜的离子屏障破坏来检测凋亡介导的膜紊乱。ISFET测定法与常规细胞毒性测定法的比较将直接膜损伤的细胞死亡与其他细胞器损伤的细胞死亡区分开来。我们的基于单元的晶体管系统快速且对质膜的离子泄漏敏感，这是因为质子和铵离子的流体动力学尺寸小，可作为指示剂。