ABSTRACT
In this chapter, a correlation between the ionic radius of the metal-complexing in double-decker phthalocyanines and positions of maxima Q-bands in the electronic absorption spectra were determined in dimethylformamide and chloroform. The increasing of ionic radius from holmium to lutetium caused a regular change in the position of the maxima Q-bands in the absorption spectra. The behavior of metal diphthalocyaninates in supramolecular systems was also investigated. It was revealed that a new band shifted to the red region appeared in absorption spectra of sandwich phthalocyaninates of lutetium, erbium and ytterbium in albumin solution. This particular behavior allows us to consider phthalocyanines as prototype of sensitive biosensor system.
