LATERAL FLOW ASSAY APPARATUS AND METHOD, AND SENSOR THEREFOR

An apparatus for electrochemically detecting and/or measuring an analyte (e.g. melatonin) in a fluid sample has a dry porous carrier that permits flow of a fluid sample by capillary action to biosensor (e.g. an analyte detection electrode set). The biosensor has a working electrode and a counter electrode disposed across the carrier in a non-parallel direction in relation to a direction of fluid flow such that the fluid sample crosses at least the working electrode embedded in the carrier. The working electrode has an analyte-specific binder immobilized on an electrically conductive material and the biosensor is configured to electrochemically, e.g. voltammetrically, detect the presence of and/or measure the amount of the analyte bound at the working electrode after the fluid sample crosses the working electrode.