The complexation of aqueous metal ions relevant to biological applications. 1. Poorly soluble zinc salts and enhanced solubility with added amino acid

Abstract The effect of added amino acid (glycine, alanine and serine) on the solubility of zinc citrate, zinc succinate and zinc oxalate was investigated. Equilibrated solutions were prepared and titrated to endpoint at pH 5.5 with Na2EDTA using Xylenol Orange indicator. In every case, a significant enhancement in solubility was seen as the amino acid increased from 1 to 50 molar excess. The increase was non-linear, and, with zinc succinate, showed saturation effects. In these cases, solution composition may be more complicated than initially thought, including mixed-ligand complexes and increasing percent free metal ion as the proportion of amino acid increases.

[1]  A. Patrizi,et al.  [Clinical evaluation of the efficacy and tolerability of the ''NoAll Bimbi Pasta Trattante'' barrier cream in napkin dermatitis]. , 2007, Minerva pediatrica.

[2]  David R. Williams,et al.  The chemical speciation of zinc in human saliva: possible correlation with reduction of the symptoms of the common cold produced by zinc gluconatecontaining lozenges , 1999 .

[3]  K. O. Hagmeyer,et al.  The Role of Zinc Lozenges in Treatment of the Common Cold , 1998, The Annals of pharmacotherapy.

[4]  S. G. Novick.  Complexometric Titration of Zinc: An Analytical Chemistry Laboratory Experiment , 1997 .

[5]  J. C. Godfrey,et al.  Zinc for treating the common cold: review of all clinical trials since 1984. , 1996, Alternative therapies in health and medicine.

[6]  Soffa Vm.  Artistic expressions of illness. , 1996 .

[7]  J. C. Godfrey,et al.  How does zinc modify the common cold? Clinical observations and implications regarding mechanisms of action. , 1996, Medical hypotheses.

[8]  H. Clever,et al.  The Solubility of Some Sparingly Soluble Salts of Zinc and Cadmium in Water and in Aqueous Electrolyte Solutions , 1992 .

[9]  J. C. Godfrey,et al.  Zinc Gluconate and the Common Cold: A Controlled Clinical Study , 1992, The Journal of international medical research.

[10]  W. Al-Nakib,et al.  Prophylaxis and treatment of rhinovirus colds with zinc gluconate lozenges , 1987, The Journal of antimicrobial chemotherapy.

[11]  Pochon Jp.  Zinc- and copper-replacement therapy--a must in burns and scalds in children? , 1981 .

[12]  J. Pochon.  Zinc- and copper-replacement therapy--a must in burns and scalds in children? , 1981, Progress in pediatric surgery.

[13]  E. Lichti,et al.  Zinc concentrations within healing wounds. Significance of postoperative zincuria on availability and requirements during tissue repair. , 1970, Archives of surgery.

[14]  D. D. Perrin,et al.  Equilibria in solutions which contain a metal ion and an amino-acid , 1969 .

[15]  E. N. Maslen,et al.  The crystal structure of Cu(II) succinate dihydrate , 1966 .

[16]  G. Ostacoli,et al.  Stability of the complexes of tricarballylic and citric acids with bivalent metal ions in aqueous solution , 1964 .

[17]  J. Jordan,et al.  The Metallic Complexes of Tartrates and Citrates, their Structure and Behavior in Dilute Solutions. I. The Cupric and Nickelous Complexes , 1945 .

[18]  R. K. Cannan,et al.  Complex Formation between Carboxylic Acids and Divalent Metal Cations , 1938 .