Tetra-substituted zinc (II) phthalocyanines (2a, 3a, 5a and 6a) were synthesized by cyclotetramerization of phthalonitrile derivatives (2,3, 5 and 6). These zinc phthalocyanines (2a, 3a, 5a and 6a) were converted into their water-soluble quaternized derivatives (2b, 3b, 5b and 6b) by reaction with methyl iodide. The photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen and photodegradation quantum yields) properties of these novel compounds were investigated in dimethylsulfoxide for both non-ionic and quatenized ionic complexes and in phosphate buffer saline (PBS) for only quaternized ionic complexes. The effect of the two type substituents with different positions on the photophysical and photochemical properties of these phthalocyanines were compared in this study. (C) 2014 Elsevier B.V. All rights reserved.