Immittance Electroanalysis in Diagnostics

Abstract

Impedance derived electroanalytical assays are inherently spectroscopic (frequency resolved) and potentially exceedingly sensitive indicators of interfacial change (such as target binding at 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. Its focus is to optimize analytical potency and to enable the user to select and apply the most frequency-optimized reporter of interfacial change and to, thereafter, run rapid (optimized) analyses at single frequencies.

A dual marker label free electrochemical assay for Flavivirus dengue diagnosis

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“…impedance Z*, capacitance C*, admittance Y* and modulus M*). It is possible, within this, to obtain different transduction signals using only one data set without any reference to equivalent circuits (Santos and Bueno, 2016;Bedatty Fernandes et al, 2015;Patil et al, 2015). The benefit of using this approach is that it is, in essence, a "plug and play" concept wherein a sensor "chip" is coupled to the read out device, where an algorithm can be set up to search for the most sensitive function, simultaneously mapping its frequency response.…”

ArtinM Binding Effinities and Kinetic Interaction with Leukemia Cells: A Quartz Crystal Microbalance Bioelectroanalysis on the Cytotoxic Effect

“…Medical biology is an importante branch of biology that incorporates knowledge coming from health care, laboratory diagnostics, etc., and typically is based on specialty areas such as molecular biology, biochemistry, cell biology, cytokinetics, and so on. Electroanalysis ,,, has the capacibility to largely impact biomedical sciences in the sense it serves as a vigorous method of assaying in this area, also proving new insights and additional knowledges sometimes not possible to be achieved by assays presently operative on therein.…”

“…The detection and quantification of protein biomarkers in biological samples lies central to proteomics, drug design, early clinical diagnosis, etc., the generation of viable protein microarrays may compete with current antibody based optical commercial microarrays . These are commonly based on sandwich assays in which antigen binding to the immobilised antibody is detected through the use of a labelled secondary antibody.…”

“…These are commonly based on sandwich assays in which antigen binding to the immobilised antibody is detected through the use of a labelled secondary antibody. Though sensitive, this approach is laborious and requires a labeled secondary specific antibody for the detection of every antigen . In order to reach higher levels of sensitivity and to move to the detection by electrical methods, which are potentially cheap, portable and multiplexable, label free.…”