title: Determination of self-exchange rate of alkanethiolates in self-assembled monolayers on gold using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.
abstract: In this paper, we describe a new method for determining the exchange rates of alkanethiolates in self-assembled monolayers (SAMs) on gold using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to analyze the compositions of the alkanethiolate in SAMs rapidly and directly. In particular, to investigate the self-exchange of alkanethiols, we prepared a deuterated alkanethiol that has the same molecular properties as the non-deuterated alkanethiol but a different molecular weight. SAMs consisting of deuterated alkanethiolates were immersed in a solution of the non-deuterated alkanethiol, and the influences of the immersion time, temperature, concentration, and solvent on the self-exchange rates were investigated. Furthermore, we assessed the exchange rates among alkanethiols with different carbon chain lengths and different size of ethylene glycol units. In addition, we performed molecular dynamics simulations using a model SAM system in order to understand the molecular mechanism of the exchange process.
authors.affiliation: Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Republic of Korea.
authors.forename: Hyunook
authors.initials: H
authors.lastname: Kang
authors.affiliation: Department of Chemistry, Kwangwoon University, Seoul 139-701, Republic of Korea.
authors.forename: Yongbin
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Republic of Korea.
authors.forename: Inseong
authors.initials: I
authors.lastname: Choi
authors.affiliation: Department of Chemistry, Kwangwoon University, Seoul 139-701, Republic of Korea.
authors.forename: Rakwoo
authors.initials: R
authors.lastname: Chang
authors.affiliation: Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, Republic of Korea. Electronic address: wsyeo@konkuk.ac.kr.
authors.forename: Woon-Seok
authors.initials: WS
authors.lastname: Yeo
mesh_terms: D000473:Alkanes / Q000032:analysis*; D006046:Gold / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013438:Sulfhydryl Compounds / Q000032:analysis*
chemical_list: D000473:Alkanes; D013438:Sulfhydryl Compounds; D006046:Gold
keywords: Alkanethiol; Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry; Self-assembled monolayers; Self-exchange