title: Hydrazide and hydrazine reagents as reactive matrices for matrix-assisted laser desorption/ionization mass spectrometry to detect steroids with carbonyl groups.
abstract: Fifty-one reagents (37 hydrazides and 14 hydrazines) were examined to determine if they could function as reactive matrices for the detection of steroids with carbonyl groups in matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Among these reagents, 3-hydroxy-2-naphthoic acid hydrazide reacted most efficiently with steroids with carbonyl groups, allowing detection of them at the 1pmol level. Results from accurate mass measurement with a JMS-S3000 Spiral-TOF suggested that the ion peaks corresponding to the protonated fragment of a hydrazone were observed, in addition to the protonated molecular peaks of the resulting hydrazones ([M(D)+H](+)) and their sodium adduct ([M(D)+Na](+)). 3-Hydroxy-2-naphthoic acid hydrazide also could detect cortisol (1.93ng) spiked in a human serum certified reference material, as well as cortisone and cortisol in a human saliva sample collected in the morning. Using a combination of 3-hydroxy-2-naphthoic acid hydrazide and α- cyano-4-hydroxycinammic acid (CHCA) (3-hydroxy-2-naphthoic acid hydrazide:CHCA=4:1, v/v), even cortisone and cortisol in a human saliva sample collected in the afternoon, when levels are typically low, could be detected effectively.
authors.affiliation: Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Midorigaoka, Ikeda, Osaka 563-8577, Japan. yasushi.shigeri@aist.go.jp.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Shigeri
authors.affiliation: Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Midorigaoka, Ikeda, Osaka 563-8577, Japan. ak-yasuda@harikai.com.
authors.forename: Akikazu
authors.initials: A
authors.lastname: Yasuda
authors.affiliation: Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Midorigaoka, Ikeda, Osaka 563-8577, Japan. masamichi.sakai@scas.co.jp.
authors.forename: Masamichi
authors.initials: M
authors.lastname: Sakai
authors.affiliation: Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Midorigaoka, Ikeda, Osaka 563-8577, Japan. shinnya-ideda@mgc.co.jp.
authors.forename: Shinya
authors.initials: S
authors.lastname: Ikeda
authors.affiliation: Department of Chemistry and Materials Engineering, Kansai University, Yamate-cho, Suita, Osaka 564-8680, Japan. arak@kansai- u.ac.jp.
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Arakawa
authors.affiliation: Research Institute for Environmental Management Technology, National Institute of Advanced Industrial Science and Technology (AIST), 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan. sato-hiroaki@aist.go.jp.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Sato
authors.affiliation: National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 3, 1-1-1 Umezono, Tsukuba, Ibaraki, 305-8563, Japan. t.kinumi@aist.go.jp.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Kinumi