Superoxide Dismutase Activities of Ironporphyrins Modified with Poly (L-lysine)

Abstract

Novel superoxide dismutase (SOD) mimics, the macromolecule-ironporphyrin possessing poly(L-lysine) (PLLN) and iron tetraphenylporphyrin derivative are synthesized and their SOD activities are evaluated. The synthesis of PLLN-bound iron nicotinoylamido-fenced tetraphenylporphyrin (PLLN/FeNFP), iron pivaloylamido-fenced tetraphenylporphyrin (PLLN/FePFP) and iron tetraphenylporphyrin (PLLN/FeP) is conducted: The molar ratio of the iron tetraphenylporphyrin derivative to the structural unit of PLLN is found to be about 1/10 under the condition of this study. The rate constant, k_cat, as indicator of SOD activity is about 10⁶ M^-1 s^-1. PLLN/FePFP is shown far more capable of functioning as a SOD mimic compared to macromolecule-ironporphyrins, owing to creation of space for an active site due to the cationic polymer domain and fenced-groups.