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Inorganic plasma with physiological CO2/HCO3- buffer.

P A A P Marques·M C F Magalhães·R N Correia
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Abstract

The substitution of tris/HCl buffer by CO(2)/HCO(3)(-) buffer in inorganic plasma was studied. An appropriate gas mixture of CO(2)/N(2) was continuously bubbled in Kokubo's SBF solution prepared without addition of Tris/HCl. This method enables buffering the solution within the 7.3-7.4 pH interval and, at the same time, reaching a HCO(3)(-) concentration between 24 and 27 mmol dm(-3), which are the normal concentrations reported for blood plasma. Mineralisation studies on calcium phosphate ceramics using this solution showed that, in the presence of such hydrogencarbonate concentrations, the formation of a mineralisation layer on the ceramic occurs via a carbonated octacalcium phosphate, that evolves to carbonated hydroxyapatite. The results suggest that mineralisation studies in this new carbonate-containing simulated inorganic plasma mimic biomineralisation more closely than traditional SBF.

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BicarbonatesBlood SubstitutesBuffersCarbon DioxideCeramicsKineticsMicroscopy, Electron, ScanningSpectroscopy, Fourier Transform InfraredSurface PropertiesJournal ArticleResearch Support, Non-U.S. Gov't

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P A A P Marques, M C F Magalhães, R N Correia. 2003. Inorganic plasma with physiological CO2/HCO3- buffer.. https://doi.org/10.1016/s0142-9612(02)00539-2

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