Biosensor National Special Laboratory, Key Laboratory for Biomedical Engineering of Ministry of Education, Department of Biomedical Engineering, Zhejiang University, Hangzhou 310027, China.
Institute of Cellular and Developmental Biology, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
Biosens Bioelectron. 2018 Apr 15;102:150-156. doi: 10.1016/j.bios.2017.08.055. Epub 2017 Oct 10.
The olfactory system is a natural biosensor since its peripheral olfactory sensory neurons (OSNs) respond to the external stimuli and transmit the signals to the olfactory bulb (OB) where they are integrated and processed. The axonal connections from the OSNs expressing about 1000 different types of odorant receptors are precisely organized and sorted out onto 1800 glomeruli in the OB, from which the olfactory information is delivered to and perceived by the central nervous system. This process is carried out with particularly high sensitivity, specificity and rapidity, which can be used for explosive detection. Biomimetic olfactory biosensors use various biological components from the olfactory system as sensing elements, possessing great commercial prospects. In this study, we utilized the genetically labeled murine M72 olfactory sensory neurons with the green fluorescent protein (GFP) as sensing components and obtained long-term in vivo electrophysiological recordings from the M72 OSNs by implanting the microelectrode arrays (MEAs) into the behaving mouse's OB. The electrophysiological responses showed high reliability, reproducibility and specificity for odor detection, and particularly, the high sensitivity for the detection of odorants that contain benzene rings. Furthermore, our results indicated that it can detect trinitrotoluene (TNT) in liquid at a concentration as low as 10M and can distinguish TNT from other chemicals with a similar structure. Thus our study demonstrated that the in vivo biomimetic olfactory system could provide novel approaches to enhancing the specificity and increasing working lifespan of olfactory biosensors capable of detecting explosives.
嗅觉系统是一种天然的生物传感器，因为其外周嗅觉感觉神经元 (OSN) 对外界刺激作出反应，并将信号传输到嗅球 (OB)，在那里进行整合和处理。表达约 1000 种不同类型气味受体的 OSN 的轴突连接被精确地组织和分类到 OB 中的 1800 个小球体上，嗅觉信息从这里传递到中枢神经系统并被感知。这个过程具有特别高的灵敏度、特异性和快速性，可用于爆炸物检测。仿生嗅觉生物传感器使用嗅觉系统中的各种生物成分作为传感元件，具有巨大的商业前景。在这项研究中，我们利用带有绿色荧光蛋白 (GFP) 的遗传标记的鼠 M72 嗅觉感觉神经元作为传感元件，并通过将微电极阵列 (MEA) 植入行为小鼠的 OB 中，从 M72 OSN 获得长期的体内电生理记录。电生理反应显示出对气味检测的高可靠性、可重复性和特异性，特别是对含有苯环的气味剂具有高灵敏度。此外，我们的结果表明，它可以检测到浓度低至 10M 的液体中的三硝基甲苯 (TNT)，并且可以区分 TNT 与其他具有相似结构的化学物质。因此，我们的研究表明，体内仿生嗅觉系统可以为增强能够检测爆炸物的嗅觉生物传感器的特异性和增加工作寿命提供新的方法。
