A reagentlesscapacitive approach to electrochemical impedance spectroscopy that avoids the use of ferrocene
Excellent baseline stability (≤2% drift over 7h after an initial stabilization over 30 min) and good resistance to non-specific protein adsorption
Utilises phytic acid-doped polyaniline (PANI-Pa) as a novel redox capacitive polymer support
Tested on CRP, a well-characterised cardiac biomarker, but easily translated to any conductive surface and any biomarker of interest
Facile assembly of the PANI film via electropolymerisation
Sensitivity of the assay can be varied through manipulation of film thickness (which alters the scale and time frame measured) and assay method allows increased receptor loading compared to previous methods.
Consists of a receptor bound to the PANI-Pa film that is capable of binding the target compound
The method allows selective assaying across a range of magnitudes with a very low limit of detection (0.5 μg/mL for the biomarker CRP)