Fine-tuning of MXene-nickel oxide-reduced graphene oxide nanocomposite bioelectrode: Sensor for the detection of influenza virus and viral protein.

Influenza viruses can cause epidemics through inter-human transmission, and the social consequences of viral transmission are incalculable. Current diagnostics for virus detection commonly relies on antibodies or nucleic acid as recognition reagent. However, a more advanced and general method for the facile development of new biosensors is increasing in demand. In this study, we report the fabrication of an ultra-sensitive peptide-based nanobiosensor using a nickel oxide (NiO)-reduced graphene oxide (rGO)/MXene nanocomposite to detect active influenza viruses (H1N1 and H5N2) and viral proteins. The sensing mechanism is based on the signal inhibition, the specific interaction between H1N1 (QMGFMTSPKHSV) and H5N1 (GHPHYNNPSLQL) binding peptides anchored on the NiO-rGO/MXene/glassy carbon electrode (GCE) surface and the viral surface protein hemagglutinin (HA) is the critical factor for the decrease in the peak current of the sensor. In this strategy, the NiO-rGO/MXene nanocomposite results in synergistic signal effects, including electrical conductivity, porosity, electroactive surface area, and active site availability when viruses are deposited on the electrode. Based on these observations, the results showed that the developed nanobiosensor was capable of highly sensitive and specific detection of their corresponding influenza viruses and viral proteins with a very low detection limit (3.63 nM of H1N1 and 2.39 nM for H5N1, respectively) and good recovery. The findings demonstrate that the proposed NiO-rGO/MXene-based peptide biosensor can provide insights for developing a wide range of clinical screening tools for detecting affected patients.