Permanganate-based synthesis of manganese oxide nanoparticles in ferritin.
This paper investigates the comproportionation reaction of MnIIwith [Formula: see text] as a route for manganese oxide nanoparticle synthesis in the protein ferritin. We report that [Formula: see text] serves as the electron acceptor and reacts with MnIIin the presence of apoferritin to form manganese oxide cores inside the protein shell. Manganese loading into ferritin was studied under acidic, neutral, and basic conditions and the ratios of MnIIand permanganate were varied at each pH. The manganese-containing ferritin samples were characterized by transmission electron microscopy, UV/Vis absorption, and by measuring the band gap energies for each sample. Manganese cores were deposited inside ferritin under both the acidic and basic conditions. All resulting manganese ferritin samples were found to be indirect band gap materials with band gap energies ranging from 1.01 to 1.34 eV. An increased UV/Vis absorption around 370 nm was observed for samples formed under acidic conditions, suggestive of MnO2formation inside ferritin.
Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, United States of America.
Cameron R
CR
Olsen
Trevor J
TJ
Smith
Jacob S
JS
Embley
Jake H
JH
Maxfield
Kameron R
KR
Hansen
J Ryan
JR
Peterson
Andrew M
AM
Henrichsen
Stephen D
SD
Erickson
David C
DC
Buck
John S
JS
Colton
Richard K
RK
Watt