Analysis of Functional Groups of Porphyrins by Collision-Induced Dissociation Mass Spectrometry/Mass Spectrometry.

Abstract

Collision-induced dissociation mass spectrometry/mass spectrometry (CID-MS/MS) was effective for estimating the substituent groups of porphyrin. The substituents of the porphyrin plane, which form the pathway for an oxygen-binding reaction, are essential for its oxygen-binding affinity. The CID-MS/MS of 5,10,15-tris(o-pivalamidophen-yl)monoaminoporphyrinatocobalt and 5,10,15,20-tetrakis(o-pivalamidophenyl)porphyrinatocopper was measured, and their fragmentations were studied using B/E-constant and B(1—E)1/2E-constant linked-scan techniques. These CID-MS/MS spectra clearly show that the substituent group represents the eliminations of the alkyl and acyl radicals from the molecular ions. Thus, the CID-MS/MS technique has been proven to be useful for characterizing porphyrin substituents.