title: Online coupling of thin layer chromatography with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry: synthesis and application of a new material for the identification of carbohydrates by thin layer chromatography/matrix free material enhanced laser desorption/ionization mass spectrometry.
abstract: This article describes the online hyphenation of thin layer chromatography with matrix free material enhanced laser desorption/ionization mass spectrometry (mf-MELDI-MS), the preparation of new material for MELDI and application of this newly synthesized material using TLC/MELDI-MS for the analysis of carbohydrate reference standards and plant extracts. Samples included within these analyses are standard solutions of glucose, sucrose, raffinose and a plant extract of Quercus robur, which is used for its anti-inflammatory, anti-viral and anthelminitc properties in phytomedicine. A new material for mf-MELDI-MS is prepared by immobilizing bradykinin--a peptide, on silica gel coupled to 4-(3-triethoxysilylpropylureido)azobenzene. This modification enables the absorption of laser energy sufficient for desorption and ionization of low molecular weight molecules like carbohydrates and amino acids. The newly synthesized material delivered excellent results in respect to signal-to-noise (S/N) ratio (S/N ratio: >9/1) and sensitivity (limit of detection (LOD): lower to ng/microL). Hyphenation of TLC to MELDI-MS employing the novel developed material simultaneously as chromatographic and mass spectrometric sorbent was shown for the first time for the analysis of low molecular weight molecules like mono- and oligosaccharides.
authors.affiliation: Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens-University Innsbruck, Innrain 52a, 6020 Innsbruck, Austria.
authors.forename: Muhammad Nasimullah
authors.initials: MN
authors.lastname: Qureshi
authors.forename: Guenther
authors.initials: G
authors.lastname: Stecher
authors.forename: Christian
authors.initials: C
authors.lastname: Huck
authors.forename: Guenther K
authors.initials: GK
authors.lastname: Bonn
mesh_terms: D001391:Azo Compounds / Q000737:chemistry / Q000378:metabolism; D001555:Benzene Derivatives / Q000737:chemistry / Q000378:metabolism; D001920:Bradykinin / Q000737:chemistry / Q000378:metabolism; D002241:Carbohydrates / Q000737:chemistry*; D002855:Chromatography, Thin Layer / Q000379:methods*; D055767:Immobilized Proteins / Q000737:chemistry / Q000378:metabolism; D010936:Plant Extracts / Q000737:chemistry; D029963:Quercus / Q000737:chemistry; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D001391:Azo Compounds; D001555:Benzene Derivatives; D002241:Carbohydrates; D055767:Immobilized Proteins; D010936:Plant Extracts; D012822:Silicon Dioxide; D001920:Bradykinin