The development of a hydrogen peroxide sensor has been
considered important in biomedical and environmental applications.
It is necessary to determine hydrogen peroxide, not
only in chemical and industrial processes such as disinfection
and waste-water treatment, but also as an intermediate product
of an enzyme reaction in biochemical processes (for
example, glucose and lactate determinations). For this purpose,
many types of hydrogen peroxide sensors have been
developed. In practice, measuring hydrogen peroxide by
using an electrochemical (amperometric and potentiometric)
sensor is suitable for quick test applications. In an amperometric
sensor, hydrogen peroxide redox reactions occur at the
working electrode, for example a bare Pt wire with an
immobilized enzyme on top, by applying a suitable potential.
One of the disadvantages of the amperometric sensors is the
required high overpotential of hydrogen peroxide oxidation,
which limits the selectivity of the sensor.Away to circumvent
the selectivity problem encountered with amperometric
hydrogen peroxide detection is the application of a potentiometric
sensor. The potentiometric sensor consists of a metallic
wire and a specific electrode material on top of it. This
electrode material is electroactive with high catalytic properties
for hydrogen peroxide. The signal of the sensor should be
measured with respect to a reference electrode. To avoid the