Extraordinary behavior of 5-(3,4-dihydroxyphenyl)-10,15,20-tris(N-methylpyridinium-3-yl)porphyrin triiodide in titration with bases and in albumin oxidation

The observed rate constants of the photoinduced oxidation of albumin increased by a factor of 1.5–2 upon deprotonation of the peripheral hydroxyl groups of 5-(3,4-dihydroxyphenyl)-10,15,20-tris(N-methylpyridinium-3-yl)porphyrin triiodide compared to its phenolic form.