Reference

Photometric determination of nitrites in drinking and service water

Photometric determination of nitrites in drinking and service water. Kratochvil, Vaclav (Vyzk. Ustav Org. Synt., Pardubice-Rybitvi, Czech.). Vodni Hospod.: B, 34(11), 303-8 (Czech) 1984. CODEN: VHOBAF. ISSN: 0322-8231. DOCUMENT TYPE: Journal CA Section: 61 (Water) Section cross-reference(s): 79 The diazotization of 4-aminobenzenesulfonic acid (I) [121-57-3] and coupling of the resulting diazonium salt with either 8-phenylamino-1-naphthalenesulfonic acid (II) [82-76-8] or N-ethyl-1-naphthylamine (III) [118-44-5] was used in the photometric detn. of the NO2- concn. in water. The color intensity of the diazo dyes depended directly on the concn. of NO2-. For the diazo-I-II dye the max. light absorption was at 554 nm and it was stable for several hours. For the diazo-I-III dye the max. light absorption was at 537 nm and it was stable 24 h. The method was sensitive enough to det. 30.05 mg/L NO2- with acceptable accuracy.

Estriol assay

Estriol assay. Breglio, Susan E.; Hanamoto, Mark S. (Bio-Rad Laboratories, Inc., USA). U.S. US 4454232 A 12 Jun 1984, 6 pp. (English). (United States of America). CODEN: USXXAM. CLASS: IC: G01N033-54; G01N033-58; G01N033-60. NCL: 436504000. APPLICATION: US 82-385598 7 Jun 1982. DOCUMENT TYPE: Patent CA Section: 2 (Mammalian Hormones) Immunoassay of human serum estriol (I) [50-27-1] is improved by the addn. of a nonionic detergent and a surface-active agent to lessen inaccuracies resulting from variable serum protein in the sample. RIA of I was performed in different serum samples with various combinations of anilinonaphthalenesulfonic acid [82-76-8], sodium deoxycholate [302-95-4], Brij 35 [9002-92-0], and Tween 80 [9005-65-6]. A combination of nonionic detergent with a surface-active agent inhibited the obsd. protein interference.