Calcium: A program in basic for calculating the composition of solutions with specified free concentrations of calcium, magnesium and other divalent cations

Dean Chang, Paul S. Hsieh, David C. Dawson

Research output: Contribution to journalArticle

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A BASIC program is presented which facilitates the formulation of biologically relevant chemical solutions containing specified free concentrations of as many as three divalent metal cations (Ca2+, Mg2+ and the choice of a third divalent cation) at any pH in the presence of as many as three ligands (EGTA, ATP and GTP). The program uses the law of mass action and the absolute stability (association) constants found in the literature to calculate the total concentration of divalent metal cation needed to achieve a desired free concentration. The user enters the pH, the concentrations of the ligands used and the desired free concentrations of the divalent cations. This program was developed for use in a wide range of biological applications, particularly the rapid design of solutions which mimic certain aspects of intracellular fluid.

Original languageEnglish (US)
Pages (from-to)351-366
Number of pages16
JournalComputers in Biology and Medicine
Issue number5
StatePublished - 1988



  • ATP
  • BASIC program
  • Calcium
  • EGTA
  • Free divalent metal cation concentration
  • GTP
  • Magnesium
  • Multi-metal/multi-ligand equilibrium

ASJC Scopus subject areas

  • Computer Science Applications
  • Health Informatics

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