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What are the major products of phosphotungstic acid reduction test?

What are the major products of phosphotungstic acid reduction test?

This reagent is formed from a mixture of phosphotungstic acid and phosphomolybdic acid, which, after oxidation of the phenols, is reduced to a mixture of blue oxides of tungsten and molybdenum.

What is phosphomolybdic acid used for?

Phosphomolybdic acid is used as reagent for colorimetric determination of phenothiazine derivatives in various pharmaceutical products. The reagent oxidizes the derivative to a cationic free radical, with which it then forms a coloured salt.

What is the purpose of phosphotungstic acid?

Phosphotungstic acid is used in histology as a component for staining of cell specimens, often together with haematoxylin as PTAH. It binds to fibrin, collagen, and fibres of connective tissues, and replaces the anions of dyes from these materials, selectively decoloring them.

What is phosphotungstic acid method?

A simple reproducible method is described for the determination of uric acid in serum. Two stable reagents, sodium carbonate and dilute phosphotungstic acid, are added to a protein-free tungstic acid filtrate of serum to develop a blue color which is measured photometrically. No cyanide is used.

What kind of stain is phosphotungstic acid used for?

Phosphotungstic acid is electron dense, opaque for electrons. It is a common negative stain for viruses, nerves, polysaccharides, and other biological tissue materials for imaging by a transmission electron microscope.

What is the role of phosphotungstic acid in analytical procedures?

In a number of analytical procedures one of the roles of phosphotungstic acid is to precipitate out proteins. It has been termed a “universal” precipitant for polar proteins. Further studies showed that no precipitation occurred with α-amino groups but did occur with guanidino, ε-amino and imidazole groups.

What is the linear formula for phosphotungstic acid?

ALDRICH Sodium phosphotungstate octadecahydrate MilliporeSigma Synonym(s): Tungstophosphoric acid sodium salt octadecahydrate Linear Formula: ~ 2Na 2 O-+P 2 O 5 -+12WO 3 -+18H 2 O

How is phosphotungstic acid prepared from a hexahydrate?

Further investigation showed that the compound was a hexahydrate not a pentahydrate as Keggin had proposed. Phosphotungstic acid can be prepared by the reaction of sodium tungstate, Na 2 WO 4 ·2H 2 O, with phosphoric acid, H 3 PO 4, acidified with hydrochloric acid, HCl. Phosphotungstic acid solutions decompose as the pH is increased.