TY - JOUR A1 - Graf, Nora A1 - Lippitz, Andreas A1 - Gross, Thomas A1 - Pippig, F. A1 - Holländer, A. A1 - Unger, Wolfgang T1 - Determination of accessible amino groups on surfaces by chemical derivatization with 3,5-bis(trifluoromethyl)phenyl isothiocyanate and XPS/NEXAFS analysis N2 - The determination of amino groups on surfaces capable of binding biomolecules is important for the understanding and optimization of technologically relevant coupling processes. In this study, three different types of amino-functionalized model surfaces, amino thiolate on Au, amino siloxane on Si, and polyethylene (PE) foils and films reacted with 1,2-diaminoethane (DAE) were derivatized with 3,5-bis(trifluoromethyl)phenyl isothiocyanate. Subsequently, these samples were analyzed by chemical derivatization X-ray photoelectron spectroscopy (CD-XPS) and near-edge X-ray absorption fine structure spectroscopy (NEXAFS). The determination of amino groups by this analytical approach allows gaining insight into the availability of groups on surfaces that can actually serve as attachment sites for biomolecules in technical applications. In the case of the amino thiolate on Au, almost 90% of the expected amino groups were detected by CD-XPS. Investigation of the amino siloxane films revealed lower yields for the derivatization reaction in the order of 30%. The lowered reaction yields are thought to be due to interactions between the amino siloxane`s amino and silanol groups or the underlying substrate, making them inaccessible to the derivatization agent. The aminated PE samples are characterized by a complex surface chemistry and structure, and reaction yields of the derivatization reaction cannot be unequivocally derived. However, 1-3% of the total carbon atoms in the surface layer were found to be bound to amino groups accessible to the derivatization agent. It can be concluded that, depending on the detailed character of the investigated amino-terminated surface, the amount of amino groups accessible to CD-XPS can be substantially lower than the total amount of amino groups present at the surface. KW - XPS/ESCA KW - NEXAFS/XANES KW - CD-XPS KW - Amino-functionalized surfaces KW - SAM PY - 2010 DO - https://doi.org/10.1007/s00216-009-3233-7 SN - 1618-2642 SN - 1618-2650 VL - 396 IS - 2 SP - 725 EP - 738 PB - Springer CY - Berlin AN - OPUS4-20744 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dietrich, Paul A1 - Horlacher, T. A1 - Gross, Thomas A1 - Wirth, Thomas A1 - Castelli, R. A1 - Shard, A.G. A1 - Alexander, M. A1 - Seeberger, P.H. A1 - Unger, Wolfgang T1 - Surface analytical characterization of carbohydrate microarrays N2 - Microarrays are a versatile platform for diagnostics and high-throughput analysis. Carbohydrate microarrays are valuable tools to investigate interactions with other molecules since many glycans are involved in fundamental biological processes. A combined X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) surface analysis was used to investigate the basic steps in the production of carbohydrate microarrays. The preparation included coupling of a thiol-terminated mannoside to maleimide-functionalized glass surfaces derived from γ-aminopropyl silane (GAPS) slides. XPS results clearly demonstrate successful chemical modification in each fabrication step, and ToF-SIMS imaging revealed immobilized carbohydrates in the spotted regions of the final microarray. KW - Carbohydrates KW - Microarrays KW - XPS KW - ToF-SIMS KW - Nona-mannoside KW - Maleimide surfaces KW - Surface analysis PY - 2010 DO - https://doi.org/10.1002/sia.3255 SN - 0142-2421 SN - 1096-9918 VL - 42 SP - 1188 EP - 1192 PB - Wiley CY - Chichester AN - OPUS4-21500 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul A1 - Horlacher, T. A1 - Gross, Thomas A1 - Wirth, Thomas A1 - Castelli, R. A1 - Shard, A.G. A1 - Alexander, M. A1 - Seeberger, P. H. A1 - Unger, Wolfgang T1 - Optimization of the performance of carbohydrate microarrays by surface chemical analysis T2 - 12th Status Seminar "Chip Technologies, Sequencing and Functional Genomics" der DECHEMA e. V. CY - Frankfurt am Main, Germany DA - 2010-02-04 PY - 2010 AN - OPUS4-20806 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Meyer-Plath, Asmus A1 - Hanelt, Sven A1 - Illgen, René A1 - Jäger, Christian A1 - Mach, Reinhard A1 - Orts Gil, Guillermo A1 - Unger, Wolfgang T1 - Physikalisch-chemische Charakterisierung von CNT T2 - Inno. CNT Jahrestagung CY - Marl (North Rhine-Westphalia), Germany DA - 2010-01-20 PY - 2010 AN - OPUS4-20860 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Min, Hyegeun A1 - Wettmarshausen, Sascha A1 - Friedrich, Jörg F. A1 - Unger, Wolfgang T1 - A ToF-SIMS Study of the Deuterium-Hydrogen Exchange Induced by Ammonia Plasma Treatment of Simple Polyolefines T2 - SIMS Europe 2010 - 7th European Workshop on Secondary Ion Mass Spectrometry CY - Münster, Germany DA - 2010-09-19 PY - 2010 AN - OPUS4-21987 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Straub, Franka A1 - Wirth, Thomas A1 - Unger, Wolfgang T1 - TOF-SIMS mapping of stainless steel microstructures T2 - SIMS EUROPE 2010 - 7th European Workshop on Secondary Ion Mass Spectrometry CY - Münster, Germany DA - 2010-09-19 PY - 2010 AN - OPUS4-22011 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Girard-Lauriault, Pierre-Luc A1 - Retzko, Iris A1 - Swaraj, Sufal A1 - Matsubayashi, N. A1 - Gross, Thomas A1 - Mix, Renate A1 - Unger, Wolfgang T1 - Non-destructive In-Depth Chemical Characterization of Air Exposed Plasma Polymers by Energy Resolved XPS T2 - Twelfth International Conference on Plasma Surface Engineering CY - Garmisch-Partenkirchen, Germany DA - 2010-09-13 PY - 2010 AN - OPUS4-21424 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Poppenberg, J. A1 - Richter, S. A1 - Traulsen, H.-H. A1 - Darlatt, Erik A1 - Sattler, D. A1 - Unger, Wolfgang A1 - Schalley, C. A. T1 - Layer-by-Layer Self Assembly of Macrocycles and Rotaxanes on Gold Surfaces T2 - 24th Conference of the European Colloid and Interface Society CY - Prague, Czech Republic DA - 2010-09-05 PY - 2010 AN - OPUS4-21384 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Wolfgang T1 - ISO/TC 201 - Inhalte und Stand der Dinge T2 - DIN-Workshop: Chemische Oberflächenanalyse - Ist eine Vertretung deutscher Interessen in der Internationalen Normung notwendig? CY - Berlin, Germany DA - 2010-04-19 PY - 2010 AN - OPUS4-21185 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Wolfgang T1 - Einsatz molekularer Monoschichten in BAM - AG Schicht- und Oberflächenanalytik T2 - DFG-Rundgespräch "Molekulare Monoschichten" CY - Günzburg, Germany DA - 2010-07-12 PY - 2010 AN - OPUS4-23069 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -