The invention relates to a transdermal analyte monitoring system comprising amedium adapted to interface with a biological membrane and to receive ananalyte from the biological membrane and an electrode assembly comprising aplurality of electrodes, wherein the medium is adapted to react continuouslywith the analyte, an electrical signal is detected by the electrode assembly,and the electrical signal correlates to an analyte value. The analyte valuemay be the flux of the analyte through the biological membrane or theconcentration of the analyte in a body fluid of a subject. The medium maycomprise a vinyl acetate based hydrogel, an agarose based hydrogel, or apolyethylene glycol diacrylate (PEG-DA) based hydrogel, for example. Thesurface region of the electrode may comprise pure platinum. The system mayinclude an interference filter located between the biological membrane and theelectrode assembly for reducing interference in the system. The system maycomprise a processor programmed to implement an error correction method thatcorrects for sensor drift.
