Abstract The gist of biosensor is the sensing layer itself due to the ability to sense bio components such as bacteria. Graphene is an example of a promising material used as biosensor. Graphene material possess unique and superior properties and promised material to use as sensing layer due to its advantages in conductivity and large surface area. Escherichia coli is a group of bacteria causes harmful disease to human health due to its spreading in environment through faecal contaminated water. This study reports on biocompatibility of graphene against E. coli through visible growth inhibitory test and SEM image that evidently showed no inhibition growth and undamaged bacteria cell. Graphene wettability over water contact angle performed by hydrophobicity with 108.90° which preferably attached by the cells due to its surface energy condition. Negativity charge of bacteria enables to induce the holes of graphene then formed ohmic contact between the sheets and electrode. Based on its resistance, graphene could detect E. coli with limit detection of 4 CFU. Therefore, a compact and portable design of E. coli sensor was successfully fabricated with the device average error about 12.23%.

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一种以石墨烯为传感材料的新型便携式大肠杆菌细菌传感器

摘要 生物传感器的本质是传感层本身，因为它具有感知细菌等生物成分的能力。石墨烯是用作生物传感器的有前途的材料的一个例子。石墨烯材料具有独特而优越的性能，由于其导电性和大表面积的优势，有望用作传感层。大肠杆菌是一组通过粪便污染的水在环境中传播，从而对人类健康造成有害疾病的细菌。本研究通过可见的生长抑制试验和 SEM 图像报告了石墨烯对大肠杆菌的生物相容性，显然没有抑制生长和未损坏的细菌细胞。石墨烯对水接触角的润湿性由疏水性实现，108.90° 由于其表面能条件，优选由细胞附着。细菌的负电荷能够诱导石墨烯的空穴，然后在片材和电极之间形成欧姆接触。基于其抗性，石墨烯可以检测大肠杆菌，检测限为 4 CFU。因此，成功制造了一种紧凑便携的大肠杆菌传感器设计，设备平均误差约为 12.23%。