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Solving buffering problems with Mathematica software.

S J Kleene·H C Cejtin
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Abstract

Determining ionic concentrations in buffered solutions usually reduces to solving a set of simultaneous polynomial equations. Mathematica software offers a convenient method for doing this. Using buffering of Ca2+ by ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) as an example, we provide a Mathematica script to estimate the apparent association constant. A second example shows how to calculate free ion concentrations when two ligands (Ca2+ and Mg2+) compete for one chelator (EGTA). Finally, the concentrations of all species are determined in a complex mixture containing Ca2+, EGTA, and calmodulin, a protein with four Ca(2+)-binding sites. Modifying the examples presented should allow analysis of most practical buffering problems.

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AlgorithmsBuffersCalciumEgtazic AcidOsmolar ConcentrationSoftwareJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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S J Kleene, H C Cejtin. 1994-11-01. Solving buffering problems with Mathematica software.. https://doi.org/10.1006/abio.1994.1497

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