Spectral properties and photophysical behaviour of water soluble cationic Mg(II) and Al(III) phthalocyanines

Idowu M. A. , Arslanoglu Y. , NYOKONG T.

CENTRAL EUROPEAN JOURNAL OF CHEMISTRY, vol.12, no.3, pp.403-415, 2014 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 12 Issue: 3
  • Publication Date: 2014
  • Doi Number: 10.2478/s11532-013-0388-z
  • Page Numbers: pp.403-415


Peripherally and non-peripherally tetrasubstituted-[(N-methyl-2-pyridylthio)]phthalocyaninato magnesium (II) (5 and 6) and chloro aluminium (III) (7 and 8) tetraiodide have been synthesized and characterized. The photophysical properties of the complexes in dimethyl sulfoxide (DMSO) and aqueous medium in the presence and absence of cremophore EL have been studied. These complexes show high solubility in aqueous medium though they were aggregated. The triplet state quantum yields (F-T) and the triplet lifetimes (t(T)) were found to be higher in DMSO with I broken vertical bar(T) ranging from 0.32 to 0.51, while t(T) ranged from 282 to 622 ms in DMSO, compared to aqueous medium (pH 7.4 buffer) where I broken vertical bar(T) ranged from 0.15 to 0.19 and t(T) from 26 to 35 ms. Addition of cremophore EL in aqueous solution resulted in partial disaggregation and increased photoactivity. The fluorescence lifetimes of the complexes showed strong dependence on their immediate environment. The ionic magnesium(II) and aluminium(III) phthalocyanines strongly bind to bovine serum albumin (BSA).