US 12,130,267 B2
Analyzing method for azo compound
Tetsuo Tanigawa, Kyoto (JP); Natsuyo Asano, Kyoto (JP); Zhao Qi Zhan, Singapore (SG); Yin Ling Chew, Singapore (SG); Jun Xiang Lee, Singapore (SG); and Jie Xing, Singapore (SG)
Assigned to SHIMADZU CORPORATION, Kyoto (JP)
Appl. No. 17/296,642
Filed by SHIMADZU CORPORATION, Kyoto (JP)
PCT Filed Oct. 30, 2019, PCT No. PCT/JP2019/042673
§ 371(c)(1), (2) Date May 25, 2021,
PCT Pub. No. WO2020/110584, PCT Pub. Date Jun. 4, 2020.
Claims priority of application No. 10201810673S (SG), filed on Nov. 28, 2018.
Prior Publication US 2022/0026404 A1, Jan. 27, 2022
Int. Cl. G01N 30/34 (2006.01); B01D 15/32 (2006.01); G01N 30/02 (2006.01); G01N 30/60 (2006.01); G01N 30/72 (2006.01); G01N 30/88 (2006.01)
CPC G01N 30/34 (2013.01) [B01D 15/325 (2013.01); G01N 30/7233 (2013.01); G01N 30/88 (2013.01); G01N 2030/027 (2013.01); G01N 2030/6013 (2013.01); G01N 2030/884 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A method for analyzing a plurality of kinds of azo compounds in a sample, comprising:
a first analyzing step in which a first analysis is performed for a target sample to detect a plurality of azo compounds in the sample, using a liquid chromatograph in which a liquid chromatograph with a reverse phase column, the liquid chromatograph being coupled with a mass spectrometer; and
a second analyzing step in which a second analysis is performed for the target sample to detect a plurality of azo compounds which are contained in the sample, using a liquid chromatograph in which a liquid chromatograph with a reverse phase column, the liquid chromatograph being coupled with a mass spectrometer,
wherein:
the first analyzing step is a gradient analysis using, as two mobile phases, a first mobile phase which is either an aqueous ammonium acetate solution or an aqueous ammonium formate solution, and a second mobile phase which is a mixture of an organic solvent and either an aqueous ammonium acetate solution or an aqueous ammonium formate solution; the second analysis is a gradient analysis using, as two mobile phases, a first mobile phase which is an aqueous solution of ammonia or ammonium salt with pH greater than 7.0, and a second mobile phase which is an organic solvent; and the azo compounds to be detected in the second analysis are azo compounds each of which produces a primary aromatic amine hazardous to a human body through a reduction reaction, the azo compounds including include azo compounds contained in seven kinds of azo dyes which respectively have following color index substance names: Acid Red 26, Acid Red 114, Direct Red 28, Direct Blue 6, Direct Black 38, Direct Brown 95 and Navy Blue 1.