Smart Flexible Electrochemical Biosensors to be Integrated in Face Masks for Personalized Detection of Coronavirus (COVID-19)

Abstract

Severe acute syndrome coronavirus 2 (SARS-CoV-2 or 2019-nCoV) is the most lethal disease of 2020 that challenged the health systems of all around the globe. Therefore, early detection of the infection is a key issue for a successful control and manage the COVid-19 disease. Currently, the available detection system is based on real-time reverse transcription− polymerase chain reaction (RT-PCR), which is selective and characterized by high sensitivity. However, it requires long analysis time, specialized technical staff to take samples and processing and is expensive for large scale screening of multiple samples. Therefore, there is an utmost and urgency for the development of rapid and cost-effective self-detecting systems without the need to resort to hospital and technical staff. To achieve these goals, electrochemical biosensors have become an appealing choice due to their high sensitivity, selectivity, low-cost, ease of use and possibility of miniaturization. Herein, we propose a smart, flexible antibody-based electrochemical device enabling the detection of COVID-19 rapidly and that can be easily integrated in patients’ masks for personalized detection. The detection system is based on a flexible PET/paper graphene electrode, modified with two-dimensional materials (composites/conducting polymers), functionalized by a suitable antibody for the detection of COVid-19 related Spike protein. In fact, SARS-CoV-2 uses angiotensin-converting enzyme II (ACE2) as a cellular entry receptor; ACE2 is also a well-known host cell receptor for SARS-CoV. SARS-CoV-2 colocalizes with ACE2 in animal cells, and its spike (S) protein binds ACE2 with high affinity. PET/graphene paper modified with two-dimensional nanostructured materials, having high surface to volume ratios, are employed for the direct attachment of monoclonal antibodies for the detection of the spike protein. The attachment of the antibody is performed by using enzyme linkers like PBASE or by functionalizing antibodies with the desired functional groups (NH2 or SH, etc.). The electrochemical assay is based on the decrease of the current intensity of a redox mediator, added on purpose in the medium, upon binding of the Spike protein to the antigen immobilized on the sensor surface, because of the enhanced coverage of the electrode surface with the bulky sized Spike protein.