INVESTIGADORES
DAIER Veronica Andrea
artículos
Título:
Preparation, characterization and activity of CuZn and Cu2 superoxide dismutase mimics encapsulated in mesoporous silica
Autor/es:
PATRIARCA, MATÍAS; DAIER, VERÓNICA; CAMÍ, GERARDO; RIVIÈRE, ERIC; HUREAU, CHRISTELLE; SIGNORELLA, SANDRA
Revista:
JOURNAL OF INORGANIC BIOCHEMISTRY
Editorial:
ELSEVIER SCIENCE INC
Referencias:
Año: 2020 vol. 207
ISSN:
0162-0134
Resumen:
Encapsulation of three superoxide dismutase (SOD) functional mimics, [CuZn(dien)2(μ-Im)(ClO4)2]ClO4 (1),[Cu2(dien)2(μ-Im) (ClO4)2]ClO4 (2) (Im = imidazolate, dien = diethylenetriamine), and [CuZn(salpn)Cl2] (3)(H2salpn = 1,3-bis(salicylideneamino)propane) in mesoporous MCM-41 silica afforded three hybrid catalysts 1@MCM-41, 2@MCM-41 and 3@MCM-41. Spectroscopic and magnetic analyses of these materials confirmed the metal centers of the complexes keep the coordination sphere after insertion into the MCM-41 silica matrix. For the imidazolate-bridged complexes the silica channels restraint the relative orientation of the two metal ions.While 3@MCM-41 shows SOD activity significantly lower than the host-free complex, insertion of the imidazolate- bridged CuZn or Cu2 complexes by ion exchange onto mesoporous MCM-41 silica affords durable and recoverable supported catalysts with much better SOD activity than the free complexes. For confined imidazolate- bridged complexes, 1@MCM-41 and 2@MCM-41, the small pore size of the silica matrix improves the SOD activity more than a host with larger pores. This high SOD activity is attributed to the close-fitting of the complexes into the nanochannels of MCM-41 silica that favors the Cu active site and HImZn(or Cu) group stay in close proximity during catalysis.