Porfirino rūgštiniame vandeniniame tirpale stabilumo ir agregacijos būvio optiniai tyrimai

Abstract

Stability and aggregation forms of aqueous solution (pH 2.5) of meso-tetra (4-sulfonatophenyl) porphine were studied by measuring the absorption spectra in UV-VIS range 200-800 nm. Longduration (up to 10 days) temporal variations of the optical features were examined 10 days after preparation of solution and interpreted by the change of the forms (from diprotonated to free-base) and aggregation state (J-aggregates and monomers) of porphyrin. The observed effects were explained by the variation of acidity of the aqueous solution induced by the change of the composition of solution and due to the possible influence of photodegradation. It was also concluded that J-aggregates are most favorably adsorbed on the solid substrates from aqueous solution of porphyrin.