The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



organic reagents used in analytical chemistry. There are three different reagents: arsenazo-I,-II, and -III. Arsenazo is a fine crystalline powder, dark brown or black (arsenazo-lll) in color, easily soluble in water. All arsenazo reagents are derivatives of chromotropic acid (1) and various substitutes of phenolarsenic acid (2). Arsenazo-II and arsenazo-III differ from arsenazo-I (3) by their more complicated structure. Arsenazo forms colored solutions with

many elements; these solutions can be used for the photometric determination (arsenazo -I) of the elements. They form strong complexes with such elements as thorium, zirconium, and hafnium.


Kuznetsov, V. I., and V. G. Tiptsova. “Arsenazo.” In Kratkaia khimicheskaia entsiklopediia, vol. 1. Moscow, 1961. Page 292.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
After shaking for 4 h of equilibration time the beads were separated from the uranyl solution and the raffinate solution was treated with complexing agent Arsenazo (III) to determine the left-over concentration of uranium.
Serum calcium, phosphorus and alkaline phosphate were estimated using Olympus AU 400 chemistry autoanalyzer, serum calcium by photometric color (Arsenazo method) test, serum inorganicphosphorus by photometric Ultraviolet test (phosphomolybdate method) & serum alkaline phosphate by kinetic colorimetrictest (p-nitrophenyl phosphate in amino methyl propanol buffer solution).
Serum calcium was estimated by colorimetric method using dye Arsenazo III by Autozyme Calcium Arsenazo III.
Summary: This work describes the liquid-liquid extraction of uranium (U) from 3 mole L-1 nitric acid media by N, N-di(2-ethyl hexyl) hexanamide (DOHA) in dodecane and subsequent determination of uranium using arsenazo III as a chromogenic reagent.
They are 1.00 mol/L HAc~ NaAc buffer solution; 1.00 mol/L NaH2PO4~Na2HPO4 buffer solution; 6.00 mol/L HCl; 4.00 mol/L [H.sub.2]S[O.sub.4]; 1.00 x [10.sup.-2] mol/L arsenazo III (C22H18As2O14N4S2).
Arsenazo III (ASA) is abis-azo metalchromogenic reagent which has been in use since 1960 for spectrophotometric determination of metal ions.
Serum P and [Ca.sup.2+] concentration was assessed using the enzymatic method as described by Spinreact S.A., Spain, and the colorimetric Arsenazo III method as described by Biomaxima S.A., Poland.
Ilkova, "Photometric determination of micro amounts of calcium with arsenazo III," Analytica Chimica Acta, vol.
Blood samples were collected by cardiac puncture for determination of total serum calcium (Calcium reaction with arsenazo III in acidic medium, forming the calcium-arsenazo III blue color; absorbance of the reaction product was measured at wavelengths of 600 or 660 nm).