Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia; Centre for Innovation in Medical Engineering (CIME), Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia.
Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia; Centre for Innovation in Medical Engineering (CIME), Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, 50603 Kuala Lumpur, Malaysia.
Biosens Bioelectron. 2018 Jun 1;107:145-152. doi: 10.1016/j.bios.2018.02.024. Epub 2018 Feb 9.
Nanowire sensors offer great potential as highly sensitive electrochemical and electronic biosensors because of their small size, high aspect ratios, and electronic properties. Nevertheless, the available methods to fabricate carbon nanowires in a controlled manner remain limited to expensive techniques. This paper presents a simple fabrication technique for sub-100 nm suspended carbon nanowire sensors by integrating electrospinning and photolithography techniques. Carbon Microelectromechanical Systems (C-MEMS) fabrication techniques allow fabrication of high aspect ratio carbon structures by patterning photoresist polymers into desired shapes and subsequent carbonization of resultant structures by pyrolysis. In our sensor platform, suspended nanowires were deposited by electrospinning while photolithography was used to fabricate support structures. We have achieved suspended carbon nanowires with sub-100 nm diameters in this study. The sensor platform was then integrated with a microfluidic chip to form a lab-on-chip device for label-free chemiresistive biosensing. We have investigated this nanoelectronics label-free biosensor's performance towards bacterial sensing by functionalization with Salmonella-specific aptamer probes. The device was tested with varying concentrations of Salmonella Typhimurium to evaluate sensitivity and various other bacteria to investigate specificity. The results showed that the sensor is highly specific and sensitive in detection of Salmonella with a detection limit of 10 CFU mL. Moreover, this proposed chemiresistive assay has a reduced turnaround time of 5 min and sample volume requirement of 5 µL which are much less than reported in the literature.
纳米线传感器由于其小尺寸、高纵横比和电子特性，在作为高度灵敏的电化学和电子生物传感器方面具有巨大的潜力。然而，以可控的方式制造碳纳米线的现有方法仍然限于昂贵的技术。本文提出了一种通过集成静电纺丝和光刻技术制造亚 100nm 悬空碳纳米线传感器的简单制造技术。碳微机电系统 (C-MEMS) 制造技术允许通过将光致抗蚀剂聚合物图案化成所需的形状并通过热解对所得结构进行碳化来制造高纵横比的碳结构。在我们的传感器平台中，通过静电纺丝沉积悬空纳米线，同时使用光刻技术制造支撑结构。在这项研究中，我们已经实现了亚 100nm 直径的悬空碳纳米线。然后，将传感器平台与微流控芯片集成，形成用于无标记化学电阻生物传感的片上实验室设备。我们通过用沙门氏菌特异性适体探针官能化来研究这种纳米电子无标记生物传感器在细菌传感方面的性能。该设备经过不同浓度的鼠伤寒沙门氏菌测试，以评估灵敏度和各种其他细菌以研究特异性。结果表明，该传感器在检测沙门氏菌方面具有高度的特异性和灵敏度，检测限为 10 CFU/mL。此外，与文献报道相比，这种提出的化学电阻测定法具有更短的检测时间（5 分钟）和更少的样品体积需求（5µL）。
