Structural analysis of Si-substituted hydroxyapatite: zeta potential and X-ray photoelectron spectroscopy

• Tipo: Artigo em Revista Científica Internacional
• Data: 2002

Autores

C. M. Botelho (Autor) Outra; Maria Ascensão Lopes (Autor) FEUP; I. R. Gibson (Autor) Outra; S. M. Best (Autor) Outra; José S. Santos (Autor) FEUP

Revista

Título: Journal of Materials Science: Materials in Medicine

Vol. 13

Páginas: 1123-1127

ISSN: 0957-4530

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 101 Citações

ISI Web of Science

Scopus - 142 Citações

Classificação Científica

FOS: Ciências da engenharia e tecnologias > Biotecnologia ambiental

Outras Informações

ID Authenticus: P-000-M8H

DOI: 10.1023/a:1021177601899

Abstract (EN): The aim of this study was to determine the effect of the incorporation of silicon on the surface charge of hydroxyapatite (HA) and to assess surface structural changes of HA and Si-HA induced by dissolution in both static and dynamic systems. X-ray photoelectron spectroscopy (XPS) analysis showed that SiO4- groups were substituted for PO43- groups in the silicon-hydroxyapatite (Si-HA) lattice according to a previously proposed substitution mechanism without the formation of other crystalline phases, such as tricalcium phosphate or calcium oxide. The substituted silicon induced a decrease in the net surface charge and the isoelectric point of HA as determined by zeta potential (ZP) measurements. At physiological pH = 7.4 the surface charge of Si-HA was significantly lowered compared to unmodified HA, i.e. - 50 +/- 5 to - 71 +/- 5 eV, caused by the presence of silicate groups in the HA lattice, which may account for a faster in vitro apatite formation using SBF testing. XPS results indicated that silicon seems to be preferentially leached out from Si-HA surface compared to other ionic species after dissolution studies in tris-buffer using a dynamic system. (C) 2002 Kluwer Academic Publishers.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 5