Attomolar sensitivity of a redox capacitive and DNA-receptive interface attained by quantum-rate signal amplification concept.

This study demonstrates the application of quantum capacitance (C) methods to develop highly sensitive genosensors. This is achieved by employing the quantum mechanical rate (ν∝e/hC) concept to enhance the signal response of a redox-active, DNA-receptive interface. In these DNA-receptive interfaces, electrons are transported through the redox-tagged component, enabling signal amplification by adding a redox probe to the sample containing the target DNA.

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

The quantum-rate model predicts a rate as a frequency for transporting electrons within molecular structures, which is governed by the ratio between the quantum of conductance and capacitance , such that = /. This frequency, as measured in a single-layer graphene appropriately modified with suitable biological receptors, can be applied as a transducer signal that ranges sensitivities within the attomole for biosensing applications. Here, we applied this label-free and reagentless biosensing transducer signal methodology for the qualitative diagnosis of COVID-19 infections, where this assay methodology was shown to be similar to the gold-standard real-time polymerase chain reaction.