title: [Azoic color reaction of flavonoids and their analytical application].
abstract: In NH4Cl-NH3 H2O buffer solution of pH 10.4, diazo salt of p-sulfodiazoben-zene chloride reacts with rutin, morin, genistin, quercetin, hesperidin, baicalin and daidzin to form color azo-compounds. These azo-compounds have an absorption maximum at 430 nm except for baicalin azo-compound, which has an absorption maximum at 380 nm. The sensitivity of azoic color reaction is reductive in the order of above flavonoids and the molar absorptivity is maximum for rutin and is minimal for daidzin among these azo-compounds, i. e. 3.28 x 10(4) and 8.3 x 10(2) L x mol(-1) x cm(-1) respectively. The proposed spectrophotometry has been applied to th determination of flavonoids in sophora seed and soybean cake. The RSDs of the method were found to be in the range of 0.75-4.48%, and the recoveries were in the range of 99.3%-105.0%.
authors.affiliation: Faculty of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510090, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Yu
authors.forename: Xiao-Kang
authors.initials: XK
authors.lastname: Chen
authors.forename: Zong-Ming
authors.initials: ZM
authors.lastname: Luo
authors.forename: Chi
authors.initials: C
authors.lastname: Yang
authors.forename: Hua-Kun
authors.initials: HK
authors.lastname: Mai
mesh_terms: D001391:Azo Compounds / Q000737:chemistry; D002623:Chemistry Techniques, Analytical; D003116:Color; D005419:Flavonoids / Q000737:chemistry*; D011794:Quercetin / Q000737:chemistry; D012431:Rutin / Q000737:chemistry; D013053:Spectrophotometry / Q000379:methods*; D047309:Flavones
chemical_list: D001391:Azo Compounds; D005419:Flavonoids; D011794:Quercetin; D012431:Rutin; C038044:baicalin; C008548:morin; D047309:Flavones