In a communication to the Chemical Society ~ one of us reported on the property of aminoacids to form insoluble phosphotungstates. In a later publication 2 the writers showed the degree of precipitability of aminoacids by means of phosphottmgstic acid, and stated that a separation of aminoacids may be accomplished by means of this reagent. The at tempt was made to apply the method to the study ...

A simple, rapid and sensitive method was proposed for online determination of tannic acid in colored tannery wastewater by automatic reference flow injection analysis. Based on the tannic acid reduction phosphotungstic acid to form blue compound in pH 12.38 alkaline solutions, the shade of blue compound is in a linear relation to the content of tannic acid at the point of the maximum absorption...

Behre and Benedict(1) developed a procedure for the determination of ergothioneine by its reaction with a phosphotungstic acid reagent, and Huntert(2) described a method based upon the reaction between the diazotized sulf anilic acid and ergothioneine. But these procedures seemed to be unsatisfactory, so in 1947 we devised a new methodt(3) based upon the conversion of the sulfur of ergothionein...

The acidity and its effects on reactivity of Keggin-type heteropolycompounds were examined by catalytic probe reactions, microcalorimetry of ammonia sorption, and density functional quantum chemical calculations. Phosphotungstic, phosphomolybdic, silicotungstic, and silicomolybdic acids were used as model compounds. The specific rates of double-bond isomerization of both 1-butene and cis-2-bute...

the performance of msu-s and its forms modified with phosphotungstic acid (hpw) and nickel (ni) for the desulfurization and denitrogenation of model diesel fuel were studied. according to the results of the characteristic tests (n2 adsorption-desorption, xrd, sem, and nh3-tpd), heteropoly acid incorporation causes higher acidity along with a negligible loss of structural aspects, while ni impre...

After aldehyde-fixation, treatment with phosphotungstic acid (PTA) in aqueous acidic medium was shown to produce an intense electron-opaque stain with minimal distortion of organelles. Mitochondrial matrix, cisternae of the endoplasmic reticulum, and the Z-band of muscle were densely stained, whereas membranes stood out in negative contrast. Staining of glycogen or lipid was not apparent. Under...

The search for a simple, cheap, and reliable method of serum uric acid estimation has continued ever since the classic thread test of Garrod (1854); for many years Folin's phosphotungstic acid method and its numerous modifications have been employed (Folin, 1930; Brown, 1945; Caraway, 1955; Beale, 1954; Henry, Sobel, and Kim, 1957; Archibald, 1957). While the technique is easy, the method is ne...

Two cases of oncocytoma of the lacrimal caruncle are presented. This benign tumour is characterized by a uniform population of epithelial cells with abundant, finely granular, eosinophilic cytoplasm. The granules stain blue with Mallorys phosphotungstic acid hematoxylin and can be identified as mitochondria by electron microscopy. An additional 35 cases from the literature are reviewed. The tum...