Assembly oxygen sensors

The second, well-known use of stabilized zirconia is in oxygen sensors. These types of devices make use of the very high ionic conductivity of Y203- or CaO-doped cubic zirconia. The sensor assembly consists of a zirconia tube with one end closed. The inside of this tube is exposed to air and the outside is exposed to the gas that requires measurement of oxygen levels. When there is a difference in oxygen partial pressure between the inside and outside, oxygen is transported across the ceramic tube. This transport results in a measurable voltage. 

G. Ashkenasy etal.. Assemblies of Hinged Iron-Porphyrins as Potential Oxygen Sensors, J. Amer. Chem. Soc. 2000, 122,1116-1122. 

Han B-H, Manners I, Winnik MA (2005) Oxygen sensors based on mesoporous silica particles on layer-by-layer self-assembled films. Chem Mater 17 3160-3171... 

Our research group recently approached the problem of radical determination starting from the determination of oxygen free radicals, in particular superoxide radical, and assembling several new kinds of electrochemical sensors and biosensors suitable for this purpose [21-24]. Firstly, a voltammetric system based on the detection of reduced cytochrome c this system was also applied to develop a... 

Microbial Cell-containing Membranes for Molecular Recognition. Suzuki et al. (87) have proposed a miocrobial sensor which consists of membrane-bound microbial cells and an electrochemical device. The assemblies of microbial sensors are similar to enzyme sensors. Two types of microbial sensors have been developed as presented In Figure 9. The first monitors the respiration activity of membrane-bound microbial cells with a Clark-type oxygen electrode. The... 

In our approach, an electrochemical interface was created by modifying a Au electrode with macrocyclic nickel(II) complex (MNC) and a diimine (NPQD) by a self-assembling technique. The former serves as a reference whereas the latter serves an indicator molecule [122], The advantage of the present system is that the dissolved oxygen does not influence the redox potential of either reference or indicator molecules and therefore dissolved oxygen need not be removed before measurement. Figure 10-31 illustrates the fabrication of the bifunctional pH sensor. The self-assembly of NPQD was electrochemically created on the electrode surface [123] and it shows a redox response at 0.23 V vs. Ag/AgCI in neutral pH (Fig. 10-32A, see Experiment 10-6, Section 10.2.4). 

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