label: 2-(4-hydroxyphenylazo)benzoic acid
label_lc: 2-(4-hydroxyphenylazo)benzoic acid
description: "An azo compound that is azobenzene in which one phenyl group is substituted at position 4 by a hydroxy group, while the other phenyl group is substituted at position 2 by a carboxy group. It is used as a matrix in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry."