Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany.
Adv Healthc Mater. 2019 Dec;8(23):e1901215. doi: 10.1002/adhm.201901215. Epub 2019 Nov 8.
Electrodes coated with poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) have been employed to measure the integrity of cellular barriers. However, a systematic experimental study of the correlation between tissue integrity and impedance of the sensing device has not yet been conducted. Using impedance spectroscopy, how the impedance ratio of the biological tissue to the recording device affects the recording ability of the latter is investigated. PEDOT:PSS-coated electrodes of various dimensions are employed and the effect of their size to their sensing efficiency is examined. The biotic/abiotic ensemble is modeled with a simple equivalent circuit and an analytical expression of the total impedance as a function of frequency is extracted. The results reveal a critical impedance ratio of the biological tissue to the sensor which allows for efficient sensing of the tissue integrity. This work provides the ground rules for improved impedance-based biosensors with optimized sensitivity.
聚（3,4-亚乙基二氧噻吩）：聚苯乙烯磺酸盐（PEDOT:PSS）涂层电极已被用于测量细胞屏障的完整性。然而，尚未对组织完整性与传感设备阻抗之间的相关性进行系统的实验研究。本研究采用阻抗谱法，研究了生物组织与记录设备的阻抗比如何影响后者的记录能力。使用了不同尺寸的 PEDOT:PSS 涂层电极，并研究了其尺寸对传感效率的影响。采用简单的等效电路对生物/非生物组合进行建模，并提取出总阻抗随频率变化的解析表达式。结果表明，生物组织与传感器之间存在一个临界阻抗比，这使得对组织完整性的有效传感成为可能。这项工作为具有优化灵敏度的基于阻抗的生物传感器提供了基本规则。
