Tobolkina EA, Skripnikova TA, Starikova AA, Shumilova GI, Pendin AA. Features of proteolytic properties of tetraphenylporphyrin complex with lanthanide group metals.
SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018;
189:227-230. [PMID:
28820975 DOI:
10.1016/j.saa.2017.08.012]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 07/27/2017] [Accepted: 08/04/2017] [Indexed: 06/07/2023]
Abstract
UNLABELLED
Demetallation of metalloporphyrin molecules is one of the essential degradation reactions in photosynthesis. The effect of metalloporphyrin nature on removal of central metals from tetraphenylporphyrin complexes based on lanthanide group metals (Dy, Er, Lu, Ho) has been studied. pH values, at which the metal ions leave the metalloporphyrin complex were established using two-phase spectrophotometric titration with potentiometric pH-control. The pH values decrease with the increase of atomic numbers of lanthanide groups, as well as with increase of 4f-electrons. The reaction of an extra ligand exchange for the hydroxide ion was studied. For Dy-, Er- and Ho-tetraphenylporphyrin complexes one particle of extra ligand coordinates with one porphyrin complex. A complex with dimeric particles can be formed for the system of Lu-tetraphenylporphyrin. Constants of the ion exchange reactions were calculated.
SYNOPSIS
The effect of metalloporphyrin nature on removal of central metals from tetraphenylporphyrin complexes based on lanthanide group metals (Dy, Er, Lu, Ho) has been studied. The heterophase reaction of ion-selective electrodes were calculated, as well as the reaction of an extra ligand exchange for the hydroxide ion.
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