Reagentless Quantum-Rate-Based Electrochemical Signal of Graphene for Detecting SARS-CoV-2 Infection Using Nasal Swab...

Area of Science:

• * Physics-based biosensing utilizing quantum mechanics principles.
• * Development of advanced electrochemical biosensor platforms.

Background:

• * The quantum-rate model describes electron transport frequency (k) based on quantum conductance (G) and quantum capacitance (Cq).
• * Graphene-based biosensors offer high sensitivity for detecting biomarkers.
• * Existing diagnostic methods for infectious diseases require improvement in speed and accessibility.

Purpose of the Study:

• * To apply the quantum-rate model as a label-free, reagentless biosensing transducer for COVID-19 diagnosis.
• * To evaluate the performance of this novel biosensor against the gold-standard real-time polymerase chain reaction (PCR).
• * To explore the potential of this technology for point-of-care and internet-of-things (IoT) applications.

Main Methods:

• * Utilized single-layer graphene modified with biological receptors.
• * Measured electron transport frequency (k = G/Cq) as a biosensing signal.
• * Detected SARS-CoV-2 spike (S) and nucleocapsid (N) proteins from patient samples.

Main Results:

• * The quantum-rate biosensor demonstrated attomole sensitivity.
• * Qualitative diagnosis of COVID-19 showed 80% sensitivity and 77% specificity.
• * Assay results were comparable to real-time PCR.

Conclusions:

• * The quantum-rate biosensor is a viable label-free and reagentless platform for COVID-19 detection.
• * The technology is suitable for miniaturization and real-time applications, enabling point-of-care diagnostics.
• * This approach facilitates rapid development of assays for endemic and pandemic disease surveillance.