Photometric reagents

The differentiation of analytical signal in the photometry enables one to use non-specific reagents for the sensitive, selective and express determination of metals in the form of their intensively coloured complexes. The typical representative of such reagents is 4-(2-pyridylazo)-resorcinol (PAR). We have developed the methodics for the determination of some metals in the drinking water which employ the PAR as the photometric reagent and the differentiation of optical density of the mixture of coloured complexes by means of combined multiwave photometry and the specific destmction of the complexes caused by the change of the reaction medium. 

Photometric methods are simple and rapid for the determination of components of active chlorine. But photometric reagents not always are enough sensitive and reliable. 

We proposed new photometric reagent 4,4 -bis(diethylamino)-thiobenzophenone (ethyl derivative of Michler s thioketone, EMT) for the determination of free chlorine and chloramines in drinking water. 

Monoarylazo and bis(arylazo) derivatives of chromotropic acid as photometric reagents. B. Bude-sinsky, Chelates Anal. Chem., 1969, 2,1-91 (178). 

Unlike 2-thiazolidinethione and its simpler derivatives, the 3 - alkyl - 5 - hydroxy - 5 - (1,2,3,4 - tetrahydroxy -n- butyl) - 2 - thiazoli-dine thiones [which are specific, photometric reagents for Cu(ID] undergo rearrangement in the presence of Cu(II) ions, to form complexes of dithiocarbamate. The analytical specificity is explained by the inability of most other metal ions to effect this rearrangement (419). 

Enzymatic methods for cholesterol measurement are precise, accurate when calibrated appropriately, and easily adapted for use on modern analyzers. Commercially available cholesterol reagents commonly combine aU of the enzymes and other required components into a single photometric reagent. The reagent usually is mixed with a 3- to 10- JLL aliquot of serum or plasma, incubated under controlled... 

Photometric reagents, 8 Photoresponsive macrocycles, 473 Phthalamide, 413,414,482 Phthalimide, 39,45,47,51, 361,413 Phthalimide protection, 47 3-Phthalimidopropyl tosylate, 54... 

The photometric reagent 2-(5-bromo-2-pyridy-lazo)-5-diethylaminophenol is used for the determination of zirconium when fosfomycin is added, it... 

The use of curcumine as photometric reagent for the determination of boron in aluminium and its alloys at concentrations above 1 j g/g is recommended... 

Ag salt [38351-46-1]. Silver diethyldithiocarbamate. SDDC Photometric reagent for As, Sb. 

Photometric reagent for aromatic amines and phenols. Cryst.(H20). Mp 153-155° dec. 

Photometric reagent for detn. of Fe and other metal ions. Cryst. (EtN02). Mp 257-258°. Related reagents Terosine (4 -phenylterphenyl) and Terosole (4,4"-dimethyl-4 -phenylterphenyl) appear to be out of use. 

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