Quantum capacitance as a reagentless molecular sensing element

The application of nanoscale capacitance as a transduction of molecular recognition relevant to molecular diagnostics is demonstrated. The energy-related signal relates directly to the electron occupation of quantized states present in readily fabricated molecular junctions such as those presented by redox switchable self-assembled molecular monolayers, reduced graphene oxide or redox-active graphene composite films, assembled on standard metallic or micro-fabricated electrodes. Sensor design is thus based on the response of a confined and resolved electronic density of states to target binding and the associated change in interfacial chemical potential. Demonstrated herein with a number of clinically important markers, this represents a new potent and ultrasensitive molecular detection enabling energy transducer principle capable of quantifying, in a single step and reagentless manner, markers within biological fluid

Quantum capacitance as a reagentless molecular sensing element

The application of nanoscale capacitance as a transduction of molecular recognition relevant to molecular diagnostics is demonstrated. The energy-related signal relates directly to the electron occupation of quantized states present in readily fabricated molecular junctions such as those presented by redox switchable self-assembled molecular monolayers, reduced graphene oxide or redox-active graphene composite films, assembled on standard metallic or micro-fabricated electrodes. Sensor design is thus based on the response of a confined and resolved electronic density of states to target binding and the associated change in interfacial chemical potential. Demonstrated herein with a number of clinically important markers, this represents a new potent and ultrasensitive molecular detection enabling energy transducer principle capable of quantifying, in a single step and reagentless manner, markers within biological fluid

Immittance Electroanalysis in diagnostics.

Impedance derived electroanalytical assays are inherently spectroscopic (frequency resolved) and potentially exceedingly sensitive indicators of interfacial change (such as target binding with an appropriate receptor). We introduce here the use of a portfolio of mathematically derived immittance functions and related components capable, from the same raw data sets, of enabling increased assay sensitivity and markedly shorter assay times in comparison to traditional impedance analyses. The methodology, applied herein to faradaic (redox probe amplified) and non-faradaic assays, requires no equivalent circuit analysis or prior assumption of response. It also enables the user to select and apply the most frequency-optimized reporter of interfacial change and to, thereafter, run rapid optimized analyses at single frequencies

Immittance Electroanalysis in diagnostics.

Impedance derived electroanalytical assays are inherently spectroscopic (frequency resolved) and potentially exceedingly sensitive indicators of interfacial change (such as target binding with an appropriate receptor). We introduce here the use of a portfolio of mathematically derived immittance functions and related components capable, from the same raw data sets, of enabling increased assay sensitivity and markedly shorter assay times in comparison to traditional impedance analyses. The methodology, applied herein to faradaic (redox probe amplified) and non-faradaic assays, requires no equivalent circuit analysis or prior assumption of response. It also enables the user to select and apply the most frequency-optimized reporter of interfacial change and to, thereafter, run rapid optimized analyses at single frequencies