Version 1
: Received: 29 April 2021 / Approved: 3 May 2021 / Online: 3 May 2021 (08:57:39 CEST)
Version 2
: Received: 24 May 2021 / Approved: 26 May 2021 / Online: 26 May 2021 (14:19:39 CEST)
Mikheev, I.V.; Sozarukova, M.M.; Izmailov, D.Y.; Kareev, I.E.; Proskurnina, E.V.; Proskurnin, M.A. Antioxidant Potential of Aqueous Dispersions of Fullerenes C60, C70, and Gd@C82. Int. J. Mol. Sci.2021, 22, 5838.
Mikheev, I.V.; Sozarukova, M.M.; Izmailov, D.Y.; Kareev, I.E.; Proskurnina, E.V.; Proskurnin, M.A. Antioxidant Potential of Aqueous Dispersions of Fullerenes C60, C70, and Gd@C82. Int. J. Mol. Sci. 2021, 22, 5838.
Abstract
The antioxidant potential (capacity and activity) of aqueous fullerene dispersions (AFD) of non-functionalized C60, C70, and Gd@C82 endofullerene (in micromolar concentration range) was estimated based on chemiluminescence measurements of the model of luminol and generation of organic radicals by 2,2’-azobis(2-amidinopropane) dihydrochloride (ABAP). The antioxidant capacity was estimated by the TRAP method, from the concentration of half-suppression, and from the suppression area in the initial period. All three approaches agree and show that the antioxidant capacity of AFDs increased in the row Gd@C82 < C70 < C60. Mathematical modeling of the long-term kinetics data was used for antioxidant activity estimation. The effect of C60 and C70 is found to be quenching of the excited product of luminol with ABAP-generated radical and not an actual antioxidant effect; quenching constants differ insignificantly. Apart from quenching with a similar constant, the AFD of Gd@C82 exhibits actual antioxidant action. The antioxidant activity in Gd@C82 is 300-fold higher than quenching constants.
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Received:
26 May 2021
Commenter:
Ivan Mikheev
Commenter's Conflict of Interests:
Author
Comment: Significant changes have been made to the - a new title of the manuscript was introduced, including the specific objects of study fullerenes C60, C70, and Gd@C82; - figures have been corrected, some of them have been made merged. Graphical abstract has been changed to clarify the main idea of this article; - section deals with obtaining and characterization of aqueous dispersions of fullerenes were moved to supplementary material; - the results section has been expanded and rearranged; - novel references for manuscript and supplementary material have been added; - the discussion section has been redesigned and written more clearly; - abstract section has been improved and redesigned.
Commenter: Ivan Mikheev
Commenter's Conflict of Interests: Author
- a new title of the manuscript was introduced, including the specific objects of study fullerenes C60, C70, and Gd@C82;
- figures have been corrected, some of them have been made merged. Graphical abstract has been changed to clarify the main idea of this article;
- section deals with obtaining and characterization of aqueous dispersions of fullerenes were moved to supplementary material;
- the results section has been expanded and rearranged;
- novel references for manuscript and supplementary material have been added;
- the discussion section has been redesigned and written more clearly;
- abstract section has been improved and redesigned.