Determination of the pKa value of the hydroxyl group in the α-hydroxycarboxylates citrate, malate and lactate by 13C NMR: implications for metal coordination in biological systems

@article{Silva2009DeterminationOT,
  title={Determination of the pKa value of the hydroxyl group in the $\alpha$-hydroxycarboxylates citrate, malate and lactate by 13C NMR: implications for metal coordination in biological systems},
  author={Andr{\'e} M. N. Silva and Xiaole Kong and R. Hider},
  journal={BioMetals},
  year={2009},
  volume={22},
  pages={771-778}
}
Citric acid is an important metal chelator of biological relevance. Citric acid helps solubilizing metals, increasing their bioavailability for plants and microbes and it is also thought to be a constituent of both the extracellular and cytoplasmic low molecular iron pools occurring in plants and vertebrates. Metal coordination by citric acid involves coordination both by the carboxylate and hydroxyl groups, of particular interest is its α-hydroxycarboxylate function. This structural feature is… Expand
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