Comparison of inert supports in laser desorption/ionization mass spectrometry of peptides ; pencil lead, porous silica gel, DIOS-chip and NALDITM target

Institut des Biomolécules Max Mousseron (IBMM), UMR 5247 CNRS-Universités Montpellier 1 et 2, Bâtiment Chimie (17), Université Montpellier 2, Place Eugène Bataillon, 34095 Montpellier Cedex 5, France.
Rapid Communications in Mass Spectrometry (Impact Factor: 2.25). 08/2009; 23(15):2371-9. DOI: 10.1002/rcm.4158
Source: PubMed


In the search for alternative inert surfaces replacing silicon chips in Desorption/Ionization On porous Silicon (DIOS)-like mass spectrometry analyses, nanostructured silicon-based NALDI chips were evaluated in Laser Desorption/Ionization (LDI) of peptides. Comparisons were made using commercially available DIOS chips (MassPREP-DIOS-target), amorphous carbon powder from lead pencil and porous silica gel used for chromatographic purposes as reference supports. A set of synthetic model peptides presenting variable amino acid sequences of various lengths was analyzed under all conditions. The LDI responses of the four 'matrix-free' techniques were compared, especially in terms of peptide detection sensitivity and overall experiment robustness.

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