Natarajan A, Molnar P, Sieverdes K, Jamshidi A, Hickman J J
Nanoscience Technology Center, University of Central Florida, Orlando, FL 32826, USA.
Toxicol In Vitro. 2006 Apr;20(3):375-81. doi: 10.1016/j.tiv.2005.08.014. Epub 2005 Sep 29.
The threat of environmental pollution, biological warfare agent dissemination and new diseases in recent decades has increased research into cell-based biosensors. The creation of this class of sensors could specifically aid the detection of toxic chemicals and their effects in the environment, such as pyrethroid pesticides. Pyrethroids are synthetic pesticides that have been used increasingly over the last decade to replace other pesticides like DDT. In this study we used a high-throughput method to detect pyrethroids by using multielectrode extracellular recordings from cardiac cells. The data from this cell-electrode hybrid system was compared to published results obtained with patch-clamp electrophysiology and also used as an alternative method to further understand pyrethroid effects. Our biosensor consisted of a confluent monolayer of cardiac myocytes cultured on microelectrode arrays (MEA) composed of 60 substrate-integrated electrodes. Spontaneous activity of these beating cells produced extracellular field potentials in the range of 100 microV to nearly 1200 microV with a beating frequency of 0.5-4 Hz. All of the tested pyrethroids; alpha-Cypermethrin, Tetramethrin and Tefluthrin, produced similar changes in the electrophysiological properties of the cardiac myocytes, namely reduced beating frequency and amplitude. The sensitivity of our toxin detection method was comparable to earlier patch-clamp studies, which indicates that, in specific applications, high-throughput extracellular methods can replace single-cell studies. Moreover, the similar effect of all three pyrethroids on the measured parameters suggests, that not only detection of the toxins but, their classification might also be possible with this method. Overall our results support the idea that whole cell biosensors might be viable alternatives when compared to current toxin detection methods.
近几十年来，环境污染、生物战剂传播和新疾病的威胁增加了对基于细胞的生物传感器的研究。这类传感器的创建可以特别有助于检测环境中的有毒化学物质及其影响，例如拟除虫菊酯类农药。拟除虫菊酯是合成农药，在过去十年中越来越多地被用于替代滴滴涕等其他农药。在本研究中，我们使用高通量方法，通过对心脏细胞进行多电极细胞外记录来检测拟除虫菊酯。将该细胞电极混合系统的数据与通过膜片钳电生理学获得的已发表结果进行比较，并用作进一步了解拟除虫菊酯作用的替代方法。我们的生物传感器由在由60个基板集成电极组成的微电极阵列（MEA）上培养的融合单层心肌细胞组成。这些跳动细胞的自发活动产生的细胞外场电位范围为100微伏至近1200微伏，跳动频率为0.5-4赫兹。所有测试的拟除虫菊酯；α-氯氰菊酯、胺菊酯和氟氯氰菊酯，均使心肌细胞的电生理特性发生类似变化，即跳动频率和幅度降低。我们毒素检测方法的灵敏度与早期的膜片钳研究相当，这表明在特定应用中，高通量细胞外方法可以取代单细胞研究。此外，所有三种拟除虫菊酯对测量参数的类似影响表明，不仅可以检测毒素，而且用这种方法也可能对它们进行分类。总体而言，我们的结果支持这样一种观点，即与目前的毒素检测方法相比，全细胞生物传感器可能是可行的替代方案。
