title: Analysis of small biomolecules and xenobiotic metabolism using converted graphene-like monolayer plates and laser desorption/ionization time-of-flight mass spectrometry.
abstract: We report a method of small molecule analysis using a converted graphene-like monolayer (CGM) plate and laser desorption/ionization time-of-flight mass spectrometry (LDI-TOF MS) without organic matrices. The CGM plate was prepared from self-assembled monolayers of biphenyl-4-thiol on gold using electron beam irradiation followed by an annealing step. The above plate was utilized for the LDI-TOF MS analyses of various small molecules and their mixtures, e.g., amino acids, sugars, fatty acids, oligoethylene glycols, and flavonoids. The CGM plate afforded high signal-to-noise ratios, good limits of detection (1pmol to 10fmol), and reusability for up to 30 cycles. As a practical application, the enzymatic activity of the cytochrome P450 2A6 (CYP2A6) enzyme in human liver microsomes was assessed in the 7-hydroxylation of coumarin using the CGM plate without other purification steps. We believe that the prepared CGM plate can be practically used with the advantages of simplicity, sensitivity, and reusability for the matrix-free analysis of small biomolecules.
authors.affiliation: Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, South Korea.
authors.forename: Hyunook
authors.initials: H
authors.lastname: Kang
authors.affiliation: Department of Physics, Konkuk University, Seoul 143-701, South Korea.
authors.forename: Hoyeol
authors.initials: H
authors.lastname: Yun
authors.affiliation: Department of Physics, Ewha Womans University, Seoul 03760, South Korea.
authors.forename: Sang Wook
authors.initials: SW
authors.lastname: Lee
authors.affiliation: Department of Bioscience and Biotechnology, Bio/Molecular Informatics Center, Konkuk University, Seoul 143-701, South Korea. Electronic address: wsyeo@konkuk.ac.kr.
authors.forename: Woon-Seok
authors.initials: WS
authors.lastname: Yeo
mesh_terms: D000596:Amino Acids / Q000032:analysis*; D002241:Carbohydrates / Q000032:analysis*; D003374:Coumarins / Q000378:metabolism*; D065637:Cytochrome P-450 CYP2A6 / Q000378:metabolism; D005227:Fatty Acids / Q000032:analysis*; D005419:Flavonoids / Q000032:analysis*; D006046:Gold / Q000737:chemistry; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D006900:Hydroxylation; D053768:Metal Nanoparticles / Q000737:chemistry; D008862:Microsomes, Liver / Q000201:enzymology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013499:Surface Properties
chemical_list: D000596:Amino Acids; D002241:Carbohydrates; D003374:Coumarins; D005227:Fatty Acids; D005419:Flavonoids; D006046:Gold; D006108:Graphite; C030123:coumarin; C585710:CYP2A6 protein, human; D065637:Cytochrome P-450 CYP2A6
keywords: Converted graphene-like monolayer; Laser desorption/ionization time-of-flight mass spectrometry; Matrix-free; Self-assembled monolayers; Small biomolecules; Xenobiotics