IMR Press / FBL / Volume 8 / Issue 6 / DOI: 10.2741/1162

Frontiers in Bioscience-Landmark (FBL) is published by IMR Press from Volume 26 Issue 5 (2021). Previous articles were published by another publisher on a subscription basis, and they are hosted by IMR Press on as a courtesy and upon agreement with Frontiers in Bioscience.

Review of the effects of pH on the synthesis of heteropoly tungstate anions
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1 Chemistry Department, Delaware State University, Dover, Delaware 19901, USA
Front. Biosci. (Landmark Ed) 2003, 8(6), 936–944;
Published: 1 September 2003

The reaction of the WO42- ion in the pH range 2 to 8 was carried out with the following metal ions individually in combination: Mn2+, Mn3+, Fe2+, Fe3+, Co2+, Co3+, Ni2+, Cu1+, Cu2+, Zn2+, Ga3+, Mg2+, In3+, RAsO32-, & RSbO32-. Some 36 heteropolyanions have been isolated in the crystalline form & characterized fully. The antiviral activity of these anions has been determined against HIV, herpes & respiratory viruses. The redox potentials for these anions have been measured by cyclic voltammetry &  documented. At pH 8, the anions adopt a Weakley structure & at pH 7, the Keggin structure is formed. At pH 6 to 7, the distorted Keggin structure, 1:1:11, is formed. Below pH 6, the distorted Dawson structure is formed. Some anions showed good antiviral activity with positive redox potentials and others with negative redox potentials. When the metal ion is attached to an organic group, a ring-type structure is formed: a 2:5, 2:6, and 1:7 heteropolytungstate.

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