10286. Zincon

Nomenclature

CAS number: 135-52-4
2-[2-[[2-(2-Hydroxy-5-sulfophenyl)diazenyl]phenylmethylene]hydrazinyl]benzoic acid; 2-carboxy-2′-hydroxy-5′-sulfoformazylbenzene; 2-[[α-(2-hydroxy-5-sulfophenylazo)-benzylidene]-hydrazino]-benzoic acid; o-[1-(2-hydroxy-5-sulfophenyl)-3-phenyl-5-formazane]benzoic acid; 2-[5-(2-hydroxy-5-sulfophenyl)-3-phenyl-1-formazyl]benzoic acid; [1-(2-hydroxy-5-sulfophenyl)-3-phenyl-5-(2-carboxyphenyl) formazan].
C20H16N4O6S; mol wt 440.43.
C 54.54%, H 3.66%, N 12.72%, O 21.80%, S 7.28%.

Description and references

Cation chelant dye; forms deep blue-colored complexes with metal ions. Preparative method: R. Wizinger, V. Biro, Helv. Chim. Acta 32, 901 (1949) DOI PubMed. Metal chelate studies: J. H. Yoe, R. M. Rush, Anal. Chim. Acta 6, 526 (1952) DOI; R. M. Rush, J. H. Yoe, Anal. Chem. 26, 1345 (1954) DOI; A. Ringbom et al., Anal. Chim. Acta 19, 525 (1958) DOI; G. K. Singhal, K. N. Tandon, Talanta 14, 1351 (1967) DOI; E. Hilario et al., J. Biochem. Biophys. Methods 21, 197 (1990) DOI PubMed; A. V. Rossi, M. Tubino, J. Braz. Chem. Soc. 7, 161 (1996). Spectrophotometric metal determn studies: M. A. Koupparis, P. I. Anagnostopoulou, Analyst 111, 1311 (1986) DOI PubMed; L. K. Shpigun et al., Anal. Chim. Acta 573-574, 360 (2006) DOI PubMed. Determn of calcium in biological samples: C. M. Corns, Ann. Clin. Biochem. 24, 591 (1987) PubMed. Protein staining applications: G. B. Smejkal, H. F. Hoff, BioTechniques 34, 486 (2003) PubMed; J.-K. Choi et al., Electrophoresis 25, 1136 (2004) DOI. Review of use as a biological stain: Conn's Biological Stains, R. W. Horobin, J. A. Kiernan, Eds. (BIOS Scientific Publishers Ltd, Oxford, UK, 10th ed., 2002) 167-168.

Chemical structure

Properties

Purple powder, mp 203° (dec). pKa1 4.0; pKa2 7.8; pKa3 15.0. Absorption max (0.1 N sodium hydroxide): 490 nm. Moderately sol in acetone, alkali hydroxide solns; sparingly sol in water; slightly sol in ethanol.

Derivative

Sodium salt.

Nomenclature

CAS number: 62625-22-3
C20H15N4NaO6S; mol wt 462.41.
C 51.95%, H 3.27%, N 12.12%, Na 4.97%, O 20.76%, S 6.93%.

Properties

Purple powder. Irritant. Absorption max (methanol): 490, 523(sh) nm. Sol in alkali hydroxide solns; slightly sol in water, ethanol. Insol in most organic solvents. Alkaline soln is orange-red.

Use

Chromogenic indicator for complexometric and spectrophotometric determn of zinc, copper, nickel, cobalt, and mercury. Also in chelometry with EDTA. Determn of calcium in biological samples. Dye for staining proteins separated by polyacrylamide gel electrophoresis.