摘要 |
The present invention provides a novel compound that makes it possible to improve ionization efficiency of hydrophobic peptide. 5-alkoxy-2- or -3-hydroxybenzoic acid represented by the following formula (I): where R is an alkyl group having 6 to 10 carbon atoms and the substituted carboxyl group and hydroxyl group are ortho or meta to each other. A matrix additive for mass spectrometry, which is represented by the above formula (I). The above additive which is added to a matrix for mass spectrometry selected from the group consisting ofα-cyano-4-hydroxycinnamic acid, 2,5-dihydroxybenzoic acid, sinapic acid, and 1,5-diaminonaphthalene. The above additive which is used for mass spectrometry of a hydrophobic peptide. |