Non-enzyme sensors

The use of immobilized non-enzyme catalysts for analytical purposes has so far been limited by two deterrent arguments, namely  

In order to circumvent both shortcomings, achieving adequate catalytic selectivity with a non-biological catalyst entails isolating both the substrate and the catalyst. On the other hand, non-enzyme catalysts are usually much 

Non-biological catalysts used for constructing flow-through sensors are typically metal oxides and complexes, in addition to some organic compounds. Most of them act via a redox effect, so they are primarily used with electrochemical sensors (amperometric ones in particular). 

Flow-through sensors used as parts of composite modified electrodes are built by evenly spreading the catalyst on a suitable support (a conducting polymer matrix) that is compatible with the detector and analyte. The matrix is deposited as a thin film on a supporting electrode surface. 

There is a wealth of literature on transport and kinetics in microhetero-geneous catalytic systems [175,176], the influence of particle size [177], and complicated situations in which both catalytic microparticles and electron-transfer mediators are dispersed in a polymer matrix [176-179]. The designs and uses of this type of flow-through sensors have been thoroughly reviewed [180,181]. 

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