Materials Science in Semiconductor Processing 115 (2020) 105116 Available online 29 April 2020 1369-8001/© 2020 Elsevier Ltd. All rights reserved. High-performance ZnO nanowires-based glucose biosensor modifed by graphene nanoplates Zahra Rafee, Ali Mosahebfard, Mohammad Hossein Sheikhi * Research Lab. for Fabrication of Advanced Semiconductor Devices, School of Electrical and Computer Engineering, Shiraz University, Shiraz, 7134851154, Iran A R T I C L E INFO Keywords: Glucose Biosensor ZnO Graphene Glucose oxidase ABSTRACT ZnO nanowires (NWs) are known to be highly sensitive to glucose due to their strong electron transfer and adsorption as well as stability and high surface to volume ratio. On the other hand, thanks to its suitable con- ductivity, and chemical stability, Graphene is the most rampant nanomaterial used in electrochemical sensors. We have previously reported the fabrication of a glucose biosensor based on ZnO NWs synthesis on an Au interdigitated electrode. In this paper, we present the modifcation of the sensor by incorporation of Graphene Nanoplates (GNPs) beneath the ZnO NWs to achieve a glucose biosensor with high profciency. The experimental results show excellent improvement in the sensor performance in glucose detection due to this modifcation. The synergetic effects of ZnO NWs and GNPs have resulted in a desirable performance by the proposed sensor. The response time of 5 s, the detection range of 0.003–30000 mg/dL and long-term electrical stability are three outstanding characteristics of the sensor. 1. Introduction Diabetes Mellitus (DM) is a chronic metabolic disease that has become a worldwide public health problem in recent years [1]. It can lead to serious complications affecting multiple organs. It may also result in signifcant morbidity and mortality [2]. DM has no defnite treatment and its management is currently limited to glucose control. Accordingly, both the diagnosis and treatment of DM require a precise determination of blood glucose levels. Besides, due to the widespread global prevalence of DM, cost-effective glucometers are of major ne- cessity. DM has two life-threatening complications: severe hyperglyce- mia and hypoglycemia, both of which can result in slipping into the state of coma or even death if not managed accordingly [3,4]. Quick detection of blood glucose level is of great importance in the mentioned conditions which magnify the importance of low response time in glucose sensors. Consequently, the development of a precise, fast, and inexpensive blood glucose sensor is essential and of major interest for bioelectronics researchers. There are different glucose biosensors such as chemiluminescent [5], surface-enhanced Raman scattering [6], electrochemical [7,8] and transistor sensors [9]. Simple fabrication, sensitivity, and portability are three prominent characteristics of these electrochemical biosensors, making them the most popular in blood glucose assessment. The enzymatic determination of glucose level requires a model enzyme. Although the Glucose oxidase (GOx) is considered as one of the most widely used model enzymes, there is a signifcant circumscription to immobilizing the GOx on electrodes due to weak electrical communi- cation between GOx’s active side and the electrode’s surface [10]. In actuality, a protein layer blocks the electron transfer by restricting the GOx’s active side. Thus, a non-physiological electron acceptor must be employed to address the electrical communication issue between the GOx and the electrode [11]. Metal oxide nanostructures with vast specifc surface area and high biocompatibility may be used in electrochemical sensors to help enzyme adsorption. This material enriched with the vast amount of redox en- zymes have been previously used to fabricate biosensors and, according to former studies, the ZnO nanostructures can potentially be considered as highly sensitive structures for glucose detection sensors due to their suitable electrochemical activity and high electron mobility (e.g. approximately 1000 cm2/V) [12–14]. Widely disparate physical and chemical-related methods have been proposed for the preparation of one-dimensional and complex ZnO nanostructures such as: nanowires [15,16], nanorods [17,18], nanobelts [19], nanotubes [20], fower-shaped [21], interconnected network-shaped [22], nanospheres [23], nanoparticles [24], and nanofakes [25]. The simplicity of the hydrothermal method and its high speed in controlling the shape and * Corresponding author. E-mail address: msheikhi@shirazu.ac.ir (M.H. Sheikhi). Contents lists available at ScienceDirect Materials Science in Semiconductor Processing journal homepage: http://www.elsevier.com/locate/mssp https://doi.org/10.1016/j.mssp.2020.105116 Received 20 January 2020; Received in revised form 5 April 2020; Accepted 6 April 2020