After characterization, they found good specificity with LOD of 2.0??10?12?mol/L in a linear range from 1.0??10?12?mol/L to 10.0??10?6?mol/L for target DNA. selecting appropriate treatments and to prevent the epidemics. During the last decade, electrochemical biosensors Ebf1 have emerged as reliable analytical devices and represent a new promising tool for the detection of different pathogenic viruses. This review summarizes the state of the art of different virus detection with currently available electrochemical detection methods. Moreover, this review discusses different fabrication techniques, detection principles, and applications of various virus biosensors. Future research also looks at the use of electrochemical biosensors regarding a potential detection kit for the rapid identification of the COVID-19. (Jarocka et al., 2013), DENV (Darwish et al., 2015), Fig mosaic virus (Haji-Hashemi et al., 2019) CX-4945 sodium salt etc. are detected by electrochemical immunosensor recently. Non-labeled electrochemical immunosensors possess a very simple and low-cost technique because it requires easy sample preparation, not too long detection procedure and no need of secondary antibody compared to labeled technique (Mazloum-Ardakani et al., 2015). The detection efficiency of label-free electrochemical immunosensors depends on the precise alignment of antibodies during the immobilization of antibodies (Shen et al., 2015). There are various immobilization techniques of antibodies, such as straight adsorption on the electrode surface, magnetic beads (MBs) or polymer matrices, SAMs, etc., that can be used. Among these techniques, SAMs of alkanethiols are widely applied techniques because this technique provides an easy way to produce strong covalent bonds, controlled arrangement, ultrathin, oriented and ordered monolayer on the surface of the electrode (Haji-Hashemi et al., 2017). Monolayers of metals like gold, silver with the sulfur compound are able to give a proper immobilization of biomolecule. In the fabrication of electrochemical biosensor, SAMs functionalized carboxylic-antibodies group with succinimide and carbodiimide are also widely used (Chinnadayyala et al., 2019). Several reports have been made for the label-free detection of the antibody-antigen complex by using electrochemical immunosensors. Among them, some applications have been discussed in this review paper. Recently, an electrochemical immunosensor has been developed for the detection of highly pathogenic coronavirus associated with the MERS-CoV (Layqah and Eissa, 2019). Many serious respiratory illnesses even death of human-caused by this coronavirus. In this work, carbon array electrodes were fabricated with AuNPs electrodeposition to increase the sensitivity of the sensor. The authors applied recombinant spike protein S1 as a biomarker for MERS CoV. Fig. 4 A illustrates the immunosensor preparation for the detection of MERS-CoV. The SEM images for the carbon array electrode surface modified with 20 CV scans and 30 CV scans at various magnifications were presented in Fig. 4B. SEM image shows the homogenous layer of spherical gold particles onto the electrode surface with an average CX-4945 sodium salt of 50?nm diameter was obtained for 20 CV scans. The stepwise modification of the antigen modified electrodes was characterized by square wave voltammetry (SWV) as shown in Fig. 4C. This immunosensor showed a LOD of 1 1.0?pg/mL and a satisfying recovery percentage. The proposed sensor also exhibited high selectivity against Influenza A and B. Open in a separate window Fig. 4 (A) Schematic drawing of COV immunosensor array chip (a), the fabrication steps of the immunosensor (b), application of the immunosensor for the virus detection (c). (B) SEM images of, AuNPs deposited on electrodes using 20 CV scans at 12000x (a) and 100,000 magnification (b); the AuNPs deposited using 30 CV scans at 12000x (c) and 100,000 magnification (d). (C) SWV in ferro/ferrocyanide redox couple of the bare carbon array electrodes (black), after AuNPs electrodeposition using 20 CV scans (red), after cysteamine attachment (green), after glutaraldehyde activation (cyan) and after immobilization of MERS-CoV (blue) antibody (Layqah and Eissa, 2019). Reproduced with permission, copyright @ Springer. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.) A highly sensitive as well as selective label-free electrochemical immunosensors for the detection of Fig mosaic virus (FMV) has been developed with a LOD of 0.03?nM (Haji-Hashemi et al., 2019). In this paper, a polyclonal antiserum (anti-FMV) against the virus nucleocapsid was immobilized at the surface of CX-4945 sodium salt the gold electrode modified with 11-mercaptoundecanoic acid (MUA) and 3-mercapto propionic acid (MPA) through carbodiimide coupling reaction. Differential pulse voltammetry (DPV) was performed in ferri/ferrocyanide solution to evaluate the electrochemical detection of FMV. Recently, Ning et al. have designed a highly sensitive sandwich-type electrochemical immunosensor.
After characterization, they found good specificity with LOD of 2