Potentiometric Biosensors Based on Molecular-Imprinted Self-Assembled Monolayer Films for Rapid Detection of Influenza A Virus and SARS-CoV-2 Spike Protein

Abstract

Rapid, yet accurate and sensitive testing has been shown to be critical in the control of spreading pandemic diseases such as COVID-19. Current methods which are highly sensitive and can differentiate different strains are slow and cannot be conveniently applied at the point of care. Rapid tests, meanwhile, require a high titer and are not sufficiently sensitive to discriminate between strains. Here, we report a rapid and facile potentiometric detection method based on nanoscale, three-dimensional molecular imprints of analytes on a self-assembled monolayer (SAM), which can deliver analyte-specific detection of both whole virions and isolated proteins in microliter amounts of bodily fluids within minutes. The detection substrate with nanoscale inverse surface patterns of analytes formed by a SAM identifies a target analyte by recognizing its surface nano- and molecular structures, which can be monitored by temporal measurement of the change in substrate open-circuit potential. The sensor unambiguously detected and differentiated H1N1 and H3N2 influenza A virions as well as the spike proteins of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Middle-East respiratory syndrome (MERS) coronavirus in human saliva with limits of detection reaching 200 PFU/mL and 100 pg/mL for the viral particles and spike proteins, respectively. The demonstrated speed and specificity of detection, combined with a low required sample volume, high sensitivity, ease of potentiometric measurement, and simple sample collection and preparation, suggest that the technique can be used as a highly effective point-of-care diagnostic platform for a fast, accurate, and specific detection of various viral pathogens and their variants.

Advances in Electrochemical Biosensors Based on Nanomaterials for Protein Biomarker Detection in Saliva

“…Potentiometric sensors incorporating a nanostructured Au coating on silicon and a MIP recognition element were proposed for the detection of various salivary biomarkers. [108,132] Hereby, the target protein is used as the template for a 3D imprinting technique applied to an Au coating with nano-roughness. The template molecules are adsorbed onto the concave areas of the Au coating, and thiols are crystallized around the template by reacting with Au and forming the binding sites of the sensor.…”

“…The sensor was demonstrated for saliva samples and exhibited a detection time shorter than 5 min. Its analytical performance in saliva has so far been shown for viral particles, namely Zika virus or Dengue virus, [132] and protein markers such as SARS-CoV-2 S proteins [108] and cancer embryonic antigen. [133] Based on carbon ink electrodes and utilizing no biomolecular probes, another approach of the potentiometric sensor was realized for 𝛼-amylase, a common disease marker analyzed from human saliva.…”

Advances in Electrochemical Nano-Biosensors for Biomedical and Environmental Applications: From Current Work to Future Perspectives

“…Using a selective bio-receptor (e.g., peptides, aptamers, antibodies, or enzymes), adaptable potentiometric sensing protocols could be designed for a wide range of different target analytes. Recently, potentiometric nano-biosensors were developed for the rapid diagnosis of COVID-19 using a three-dimensional molecular imprinted polymer (MIP) [ 29 ]. Reflecting the high selectivity of this COVID-19-potentiometric biosensor, discrimination between the targeting coronavirus and other viruses including influenza virus (H1N1 and H3N2) and Middle-East respiratory syndrome (MERS) was achieved.…”

Addressing the Silent Spread of Monkeypox Disease with Advanced Analytical Tools

“…with limit of detection less than 200 PFU mL −1 for both viruses. [ 77 ] In another study, Gomez et al. developed a microfluidic photonic integrated circuit based biosensor for detection of six viruses: classical swine fever virus (CSFV), African swine fever virus (ASFV), porcine porcine parvovirus (PPV), porcine circovirus 2 (PCV2), a reproductive and respiratory syndrome virus (PPRSV), swine influenza virus A (SIV).…”