Metallophthalocyanines thin films in array configuration for electronic optical nose applications.

The interaction between some ambient reactive compounds and organic or inorganic thin layers can cause variations in the physical properties of the chemically interactive layers. Molecules in the gas phase, which are adsorbed onto the surface or absorbed in the bulk of the thin layer, generally modify the electrical or optical or mass properties of the gas-sensitive material giving rise to a number of different kinds of chemical sensors based on different working principles. This work reports and discusses the experimental results obtained with optical absorbance measurements in ITV-Vis spectral range onto these optical sensitive layers in controlled atmosphere containing vapours. In particular, very interesting results have been obtained by optical absorption measurements carried out in the region of the typical Q band of phthalocyanines and a selectivity toward different vapours, depending both on the metal and the peripheral substituents of the macrocycle, was found. The as-manufactured sensors have been arranged in an array configuration and examples of applications for "electronic optical nose" to the analysis of some volatile organic compounds (VOC) which are of interest in food analysis are reported in this work.