Cheng Wei, Klauke Norbert, Sedgwick Helen, Smith Godfrey L, Cooper Jonathan M
Bioelectronics Research Centre, Department of Electronics and Electrical Engineering, University of Glasgow, Glasgow, UK.
Lab Chip. 2006 Nov;6(11):1424-31. doi: 10.1039/b608202e. Epub 2006 Sep 14.
A device based on five individually addressable microelectrodes, fully integrated within a microfluidic system, has been fabricated to enable the real-time measurement of ionic and metabolic fluxes from electrically active, beating single heart cells. The electrode array comprised one pair of pacing microelectrodes, used for field-stimulation of the cell, and three other microelectrodes, configured as an electrochemical lactate microbiosensor, that were used to measure the amounts of lactate produced by the heart cell. The device also allowed simultaneous in-situ microscopy, enabling optical measurements of cell contractility and fluorescence measurements of extracellular pH and cellular Ca2+. Initial experiments aimed to create a metabolic profile of the beating heart cell, and results show well defined excitation-contraction (EC) coupling at different rates. Ca2+ transients and extracellular pH measurements were obtained from continually paced single myocytes, both as a function of the rate of cell contraction. Finally, the relative amounts of intra- and extra-cellular lactate produced during field stimulation were determined, using cell electroporation where necessary.
一种基于五个可单独寻址的微电极的装置已被制造出来，该装置完全集成在一个微流体系统中，能够实时测量来自电活性、跳动的单个心脏细胞的离子通量和代谢通量。电极阵列包括一对用于对细胞进行场刺激的起搏微电极，以及另外三个配置为电化学乳酸微生物传感器的微电极，用于测量心脏细胞产生的乳酸量。该装置还允许同时进行原位显微镜观察，从而能够对细胞收缩性进行光学测量，并对细胞外pH值和细胞内Ca2+进行荧光测量。最初的实验旨在建立跳动心脏细胞的代谢图谱，结果显示在不同速率下有明确的兴奋-收缩（EC）偶联。通过连续起搏单个心肌细胞获得了Ca2+瞬变和细胞外pH测量值，它们都是细胞收缩速率的函数。最后，在必要时使用细胞电穿孔法确定了场刺激期间细胞内和细胞外产生的乳酸的相对量。
