Laboratory of Radiobiology, University Hospital for Radiotherapy and Radiation Oncology, Medical University of Innsbruck, Anichstraße 35, A-6020, Innsbruck, Austria.
University of Applied Sciences Kufstein, Andreas Hofer-Straße 7, A-6330, Kufstein, Austria.
Biomed Microdevices. 2020 Apr 24;22(2):30. doi: 10.1007/s10544-020-00486-4.
Electric cell-substrate impedance spectroscopy (ECIS) enables non-invasive and continuous read-out of electrical parameters of living tissue. The aim of the current study was to investigate the performance of interdigitated sensors with 50 μm electrode width and 50 μm inter-electrode distance made of gold, aluminium, and titanium for monitoring the barrier properties of epithelial cells in tissue culture. At first, the measurement performance of the photolithographic fabricated sensors was characterized by defined reference electrolytes. The sensors were used to monitor the electrical properties of two adherent epithelial barrier tissue models: renal proximal tubular LLC-PK1 cells, representing a normal functional transporting epithelium, and human cervical cancer-derived HeLa cells, forming non-transporting cancerous epithelial tissue. Then, the impedance spectra obtained were analysed by numerically fitting the parameters of the two different models to the measured impedance spectrum. Aluminium sensors proved to be as sensitive and consistent in repeated online-recordings for continuous cell growth and differentiation monitoring as sensors made of gold, the standard electrode material. Titanium electrodes exhibited an elevated intrinsic ohmic resistance in comparison to gold reflecting its lower electric conductivity. Analysis of impedance spectra through applying models and numerical data fitting enabled the detailed investigation of the development and properties of a functional transporting epithelial tissue using either gold or aluminium sensors. The result of the data obtained, supports the consideration of aluminium and titanium sensor materials as potential alternatives to gold sensors for advanced application of ECIS spectroscopy.
电化学细胞-基质阻抗谱（ECIS）可实现对活体组织电参数的非侵入性和连续读取。本研究旨在研究金、铝和钛制成的 50μm 电极宽度和 50μm 电极间距离的叉指传感器在监测组织培养中上皮细胞屏障特性方面的性能。首先，通过定义的参考电解质对光刻制造的传感器的测量性能进行了表征。然后，使用这些传感器监测两种贴壁上皮屏障组织模型的电特性：代表正常功能转运上皮的肾近端小管 LLC-PK1 细胞，和形成非转运性癌上皮组织的人宫颈癌衍生的 HeLa 细胞。然后，通过将两个不同模型的参数数值拟合到测量的阻抗谱上来分析获得的阻抗谱。结果表明，铝传感器在用于连续细胞生长和分化监测的重复在线记录中与金（标准电极材料）一样敏感且一致。与金相比，钛电极表现出升高的固有欧姆电阻，反映出其较低的导电性。通过应用模型和数值数据拟合分析阻抗谱，能够使用金或铝传感器详细研究功能性转运上皮组织的发展和特性。所得数据的结果支持将铝和钛传感器材料作为金传感器的潜在替代品，用于 ECIS 光谱学的高级应用。
