High selectivity detection of FMDV- SAT-2 using a newly-developed electrochemical nanosensors

Foot-and-mouth disease virus serotype South-Africa territories-2 (FMDV-SAT-2) is the most fastidious known type in Aphthovirus which is subsequently reflected in the diagnosis regime. Rapid and early diagnostic actions are usually taken in response to the FMDV outbreak to prevent the dramatic spread of the disease. Virus imprinted sensor (VIP sensor) is gathering huge attention for the selective detection of pathogens. Thus, the whole virus particles of SAT-2 together with an electropolymerized film of poly(o-phenylenediamine) (PoPD) on gold-copper modified screen-printed electrode were applied to fabricate SAT-2-virus imprinted polymer (SAT-2-VIP). The SAT-2-VIPs were fully characterized using cyclic voltammetry (CV), linear sweep voltammetry (LSV), Atomic force microscopy (AFM), Scanning electron microscope (SEM), and Fourier transform Infra-Red (FTIR) spectroscopy. Excellent selective binding affinity towards the targeted virus particle was achieved with limits of detection and quantification of 0.1 ng/mL and 0.4 ng/mL, respectively. In terms of viral interference, the sensor did not show cross-reactivity towards other animal viruses including FMDV serotype A, O, or even SAT-2 subtype Libya and the un-related virus Lumpy skin disease virus (LSDV). This high selectivity provides a sensible platform with 70 folds more sensitivity than the reference RT-PCR as revealed from the application of SAT-2-VIP sensor for rapid analysis of clinical samples with no need for treatment or equipped labs. Thus, as diagnostic and surveillance technologies, on-site point of care diagnostics for SAT-2 virus are supported.