Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Regensburg, Germany.
Biosens Bioelectron. 2013 Nov 15;49:63-70. doi: 10.1016/j.bios.2013.04.042. Epub 2013 May 3.
Label-free approaches to monitor cell-based assays provide an unprecedented, time-resolved and non-invasive view on the response of mammalian cells to chemical, biological or physical stimuli. The most widespread techniques are impedance analysis and optical sensing using evanescent waves like SPR. This study describes the combination of both in one experimental setup so that a given cell population can be monitored simultaneously for electrical and optical changes. The device is based on commercial SPR chips that are processed by photolithography to provide electrodes for impedance analysis and gold spots for surface plasmon excitation on the same substrate. Simultaneous recordings do not interfere with each other but provide independent, time-resolved information on cell shape changes (impedance) and dynamic mass redistribution (SPR) as they occur during exposure of the cells to drugs or toxins or along their normal life cycle. This study provides proof-of-concept experiments of the dual biosensor platform in two experimental settings: signals are recorded and analyzed (i) during cell attachment, spreading and differentiation of initially suspended cells and (ii) during the exposure of the mature cells to an actin cytoskeleton disrupting drug. Impedance and SPR recordings provide complementary information that can be used to trace and assign intracellular mechanisms of action.
无标记方法可实时、非侵入性地监测基于细胞的分析，观察哺乳动物细胞对化学、生物或物理刺激的反应。最广泛使用的技术是阻抗分析和使用倏逝波（如 SPR）的光学传感。本研究将这两种技术组合在一个实验装置中，以便可以同时监测给定的细胞群体的电和光变化。该设备基于商业 SPR 芯片，通过光刻处理在同一基底上提供用于阻抗分析的电极和用于表面等离子体激发的金点。同时记录不会相互干扰，而是提供有关细胞形状变化（阻抗）和动态质量重分布（SPR）的独立、实时信息，这些变化发生在细胞暴露于药物或毒素期间，或者在其正常生命周期中。本研究在两个实验设置中提供了双生物传感器平台的概念验证实验：（i）在最初悬浮的细胞附着、铺展和分化期间以及（ii）在成熟细胞暴露于破坏细胞骨架的药物期间，记录和分析信号。阻抗和 SPR 记录提供互补信息，可用于追踪和分配细胞内作用机制。
