%0 Journal Article
%A Lu, Mei
%A Zhang, Yan
%A Wang, Yiwen
%A Jiang, Miao
%A Yao, Xin
%D 2016
%T Insight
into Several Factors that Affect the Conversion between Antioxidant
and Oxidant Activities of Nanoceria
%U https://acs.figshare.com/articles/journal_contribution/Insight_into_Several_Factors_that_Affect_the_Conversion_between_Antioxidant_and_Oxidant_Activities_of_Nanoceria/3793221
%R 10.1021/acsami.6b08219.s001
%2 https://ndownloader.figshare.com/files/5906361
%K exhibit oxidant activity
%K nanoceria
%K OH
%K antioxidant activity
%X Many
conflicting results have been reported related to the antioxidant
and oxidant activities of nanoceria. On the basis of this research,
many factors might affect the antioxidant activity of nanoceria. However,
all of the factors reported only affect the antioxidant activity of
nanoceria to a limited extent or cause the antioxidant activity to
be lost. We found that several factors can induce conversion between
the protective effect and toxicity of nanoceria. At low concentrations
of hydroxyl radicals (•OH) and nanomaterials, nanoceria exhibited
antioxidant activity but could produce greater amounts of •OH
at higher •OH or nanomaterial concentrations and subsequently
exhibit oxidant activity. Moreover, the morphology and size of nanoceria
can also affect this conversion. We found that high concentrations
of •OH and nanoceria could introduce a high amount of Ce3+ in the system, which might be the reason that nanoceria
converted from exhibiting antioxidant to oxidant activity. Under this
condition, nanoceria act as a catalyst similar to Fe2+ to
promote •OH production in a Fenton system and also as a catalyst
promoter to boost Fe2+ production of additional •OH
during the redox reaction. These conclusions support a better understanding
of conflicting reports on medicinal applications for nanoceria and
promote their practical application.
%I ACS Publications