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Role of Ferric Iron in the Oxidation of Hydrocortisone by Sepiolite and Palygorskite

Published online by Cambridge University Press:  02 April 2024

J. Cornejo ,
M. C. Hermosin ,
J. L. White ,
J. R. Barnes  and
S. L. Hem
J. Cornejo*
Affiliation:
Department of Agronomy, Purdue University, West Lafayette, Indiana 47907
M. C. Hermosin*
Affiliation:
Department of Agronomy, Purdue University, West Lafayette, Indiana 47907
J. L. White
Affiliation:
Department of Agronomy, Purdue University, West Lafayette, Indiana 47907
J. R. Barnes
Affiliation:
Department of Chemistry, Purdue University, West Lafayette, Indiana 47907
S. L. Hem
Affiliation:
Department of Industrial and Physical Pharmacy, Purdue University, West Lafayette, Indiana 47907
*
4Present address: Centro de Edafologia y Biologia Aplicada del Cuarto, C.S.I.C, Apartado 1052, Sevilla, Spain.
4Present address: Centro de Edafologia y Biologia Aplicada del Cuarto, C.S.I.C, Apartado 1052, Sevilla, Spain.
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Abstract

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The role of adsorbed and structural Fe3+ in palygorskite and sepiolite with respect to the oxidation of hydrocortisone in aqueous suspension has been evaluated using electron spin resonance and UV-visible spectroscopy. Natural surface-adsorbed Fe3+ showed an important activity in the oxidation process, although smaller than octahedral Fe3+. The kinetics of oxidative degradation of hydrocortisone by palygorskite appear to be composed of two apparent first order reactions which may be associated with two kinds of sites for Fe in palygorskite. The lower oxidizing power of sepiolite for hydrocortisone degradation is due to its very low Fe3+ content.

Резюме

Резюме

Оценивалась роль адсорбированного и структурного Fe3+ в палыгорските и сепиолите по отношению к окислению гидрокортизона в водных растворах путем электронного спинового резонанса и Уф-видимой спектроскопии. Естественные Fe3+, адсорбированные на поверхности, показали значительную, хотя меньшую, чем октаэдрические Fe3+, активность в процессе окисления. Кинетика окислительной деградации гидрокортизона палыгорскитом, по-видимому, состоит из двух кажущихся первого порядка реакций, которые могут быть связаны с двумя типами мест для Fе в палыгорските. Низшая окислительная сила сепиолита для деградации гидрокортизона обусловлена его низким содержанием Fe3+. [E.C.]

Resümee

Resümee

Der Einfluß von Fe3+, das an Palygorskit und Sepiolith adsorbiert ist oder sich in deren Struktur befindet, wurde im Hinblick auf die Oxidation von Hydrocortison in wässriger Subspension mittels Elektronenspinresonanz und UV-VIS-Spektroskopie untersucht. Natürliches, an der Oberfläche adsorbiertes Fe3+ zeigt einen erheblichen Einfluß auf den Oxidationsprozeß, der jedoch kleiner ist als der von oktaedrischem Fe3+. Die Kinetik der oxidativen Degradation von Hydrocortison durch Palygorskit scheint aus zwei Reaktionen erster Ordnung zu bestehen, die anscheinend mit zwei Arten von Fe-Plätzen im Palygorskit zusammenhängen. Das geringe Oxidationsvermögen von Sepiolith bei der Hydrocortison-Degradation hängt mit dessen sehr geringem Fe3+-Gehalt zusammen. [U.W.]

Résumé

Résumé

Le rôle de Fe3+ adsorbé et structural dans la patygorskite et la sépiolite vis à vis de l'oxidation de l'hydrocortisone en suspension aqueuse a été evalué en utilisant la résonnance à spin d’électrons et la spectroscopie UV-visible. Le Fe3+ naturel adsorbé à la surface a montré une activité importante dans le procédé d'oxidation, quoique plus petite que Fe3+ octaédral. La kinétique de dégradation oxidative de l'hydrocortisone par la palygorskite semble être composée de deux réactions de premier ordre qui pourraient être associées à deux sourtes de sites pour Fe dans la palygorskite. La capacité d'oxidation moindre de la sépiolite pour la dégradation de l'hydrocortisone est due à son très has contenu en Fe3+. [D.J.]

Keywords

CatalysisElectron spin resonanceHydrocortisoneIronOxidationPalygorskiteSepiolite
Type
Research Article
Information
Clays and Clay Minerals , Volume 31 , Issue 2 , April 1983 , pp. 109 - 112
Copyright
Copyright © 1983, The Clay Minerals Society

References

Angel, B. R., Hall, P. L. and Serratosa, J. M., 1972 Electron spin resonance studies in kaolin Proc. Int. Clay Conf., Madrid, 1972 47–59.Google Scholar
Angel, B. R. and Vincent, W. E. J., 1978 Electron spin resonance studies of iron oxides associated with the surface of kaolins Clays & Clay Mineras 26 263–272.CrossRefGoogle Scholar
Berkheiser, V. and Mortland, M. M., 1975 Variability in exchange ion position in smectite: dependence on the in-terlayer solvent Clays & Clay Minerals 23 404–410.CrossRefGoogle Scholar
Cornejo, J., Hermosin, M. C., White, J. L., Peck, G. E. and Hem, S. L., 1980 Oxidative degradation of hydrocortisone in the presence of attapulgite J. Pharm. Sci. 69 945–948.CrossRefGoogle ScholarPubMed
Goodman, B. A., 1978 An investigation by Mossbauer and EPR spectroscopy of the possible presence of iron-rich impurity phases in some montmorillonites Clay Miner. 13 351–356.CrossRefGoogle Scholar
Hermosin, M. C., Cornejo, J., White, J. L. and Hem, S. L., 1981 Sepiolite: a potential excipient for drugs subject to oxidative degradation J. Pharm. Sci. 70 189–192.CrossRefGoogle ScholarPubMed
Jackson, M. L., 1956 Soil Chemical Analysis. Advanced Course 47–58.Google Scholar
Karickhoff, S. W. and Bailey, G. W., 1973 Optical absorption spectra of clay minerals Clays & Clay Minerals 21 59–79.CrossRefGoogle Scholar
McBride, M. B., 1979 Reactivity of adsorbed and structural iron in hectorite as indicated by oxidation of benzidine Clays & Clay Minerals 27 224–230.CrossRefGoogle Scholar
McBride, M. B., Mortland, M. M. and Pinnavaia, T. J., 1975 Exchange ion position in smectite: effects on electron spin resonance of structural iron Clays & Clay Minerals 23 162–164.CrossRefGoogle Scholar
Miller, J. G., Haden, W. L., Oulton, T. D. and Bradley, W. F., 1964 Oxidizing power of attapulgite clay Clays and Clay Minerals, Proc. 12th Natl. Conf., Atlanta, Georgia, 1963 New York Pergamon Press 381–395.Google Scholar
Pitman, I. H., Higuchi, T., Alton, M. and Wiley, J., 1972 Deuterium isotope effects on degradation of hydrocortisone in aqueous solution J. Pharm. Sci. 61 918–920.CrossRefGoogle ScholarPubMed
Solomon, D. H., Loft, D. C. and Swift, A. J., 1968 Reactions catalyzed by minerals. IV: The mechanism of the benzidine blue reaction in silicate minerals Clay Miner. 7 389–397.CrossRefGoogle Scholar
Takubo, T., Tadaka, T. and Sanwai, T., 1962 Stability of cortisone and hydrocortisone Yakuzaigaku 22 67–70.Google Scholar
Theng, B. K. G., 1974 The Chemistry of Clay-Organic Reactions London Adam Hilger 261–291.Google Scholar