TY - JOUR A1 - Dietrich, Paul A1 - Horlacher, T. A1 - Girard-Lauriault, Pierre-Luc A1 - Gross, Thomas A1 - Lippitz, Andreas A1 - Min, Hyegeun A1 - Wirth, Thomas A1 - Castelli, R. A1 - Seeberger, P.H. A1 - Unger, Wolfgang T1 - Adlayers of dimannoside thiols on gold: surface chemical analysis N2 - Carbohydrate films on gold based on dimannoside thiols (DMT) were prepared, and a complementary surface chemical analysis was performed in detail by X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), near-edge X-ray absorption fine structure (NEXAFS), FT-IR, and contact angle measurements in order to verify formation of ω-carbohydrate-functionalized alkylthiol films. XPS (C 1s, O 1s, and S 2p) reveals information on carbohydrate specific alkoxy (C–O) and acetal moieties (O–C–O) as well as thiolate species attached to gold. Angle-resolved synchrotron XPS was used for chemical speciation at ultimate surface sensitivity. Angle-resolved XPS analysis suggests the presence of an excess top layer composed of unbound sulfur components combined with alkyl moieties. Further support for DMT attachment on Au is given by ToF-SIMS and FT-IR analysis. Carbon and oxygen K-edge NEXAFS spectra were interpreted by applying the building block model supported by comparison to data of 1-undecanethiol, poly(vinyl alcohol), and polyoxymethylene. No linear dichroism effect was observed in the angle-resolved C K-edge NEXAFS. KW - Carbohydrates KW - Self-assembled monolayer KW - XPS KW - NEXAFS KW - ToF-SIMS KW - Surface chemical analysis PY - 2011 U6 - https://doi.org/10.1021/la104038q SN - 0743-7463 SN - 1520-5827 VL - 27 IS - 8 SP - 4808 EP - 4815 PB - American Chemical Society CY - Washington, DC AN - OPUS4-23554 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Min, Hyegeun A1 - Girard-Lauriault, Pierre-Luc A1 - Gross, Thomas A1 - Lippitz, Andreas A1 - Dietrich, Paul A1 - Unger, Wolfgang T1 - Ambient-ageing processes in amine self-assembled monolayers on microarray slides as studied by ToF-SIMS with principal component analysis, XPS, and NEXAFS spectroscopy N2 - We investigated the ageing of amine-terminated self-assembled monolayers (amine-SAMs) on different silica substrates due to exposure to different ambient gases, pressures, and/or temperatures using time-of-flight secondary ion mass spectrometry (ToF-SIMS) with principal component analysis and complementary methods of surface analysis as X-ray photoelectron spectroscopy (XPS) and near edge X-ray absorption fine structure (NEXAFS). The goal of this study is to examine the durability of primary amine groups of amine-SAMs stored in a user laboratory prior to being used as supports for biomolecule immobilization and other applications. We prepared amine-SAMs on the native oxides of silicon wafers and glass slides using 3- aminopropyl triethoxysilane, by using optimized conditions such as anhydrous organic solvent and reaction time scale of hours to avoid multilayer growth. Selected commercial amine-SAM slides have been investigated, too. When the amine-SAMs are exposed to air, oxygen incorporation occurs, followed by formation of amide groups. The formation of oxygen species due to ageing was proved by ToFSIMS, XPS, and NEXAFS findings such as CNO- secondary ion emission at m/z 42, observation of the N 1s HNC=O component peak at 400.2–400.3 eV in XPS, and, last but not least, by formation of a π*(HNC=O) resonance at 401 eV in the N K-edge X-ray absorption spectrum. It is concluded that the used multi-method approach comprising complementary ToF-SIMS, XPS, and NEXAFS analyses is well suited for a thorough study of chemical aspects of ageing phenomena of amine-SAM surfaces. KW - Amine-SAM KW - Ageing process KW - ToF-SIMS KW - NEXAFS KW - XPS PY - 2012 U6 - https://doi.org/10.1007/s00216-012-5862-5 SN - 1618-2642 SN - 1618-2650 VL - 403 IS - 2 SP - 613 EP - 623 PB - Springer CY - Berlin AN - OPUS4-25829 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Girard-Lauriault, Pierre-Luc A1 - Gross, Thomas A1 - Lippitz, Andreas A1 - Unger, Wolfgang T1 - Chemical and elemental depth profiling of very thin organic layers by constant kinetic energy XPS: a new synchrotron XPS analysis strategy N2 - We present a new synchrotron X-ray photoelectron spectroscopy strategy for surface chemical analysis of materials. Our approach is based on the acquisition of photoelectron spectra at constant kinetic energies with the help of a tunable synchrotron X-radiation source. This ensures both constant and tunable information depth for all elements in a very thin organic layer. Many of the problems known to XPS depth profiling using laboratory equipment are thereby avoided. Using our methodology, the 95% information depth, z95%, can be tuned down to about 0.7 nm in organic materials. The upper limit in our study at the HE-SGM monochromator dipole magnet beamline at the synchrotron radiation source BESSY II is about 4.3 nm. Elemental quantification is achieved through relative sensitivity factors (RSF) specific to the measurement conditions, determined either with the help of calculated photoionization cross sections and inelastic mean free paths or experimentally. The potential of the technique is demonstrated for the in-depth analysis of plasma deposited nitrogen-rich organic thin films used in biomedical applications. PY - 2012 U6 - https://doi.org/10.1021/ac300585q SN - 0003-2700 SN - 1520-6882 VL - 84 IS - 14 SP - 5984 EP - 5991 PB - American Chemical Society CY - Washington, DC AN - OPUS4-26299 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Girard-Lauriault, Pierre-Luc A1 - Swaraj, S. A1 - Retzko, I. A1 - Matsubayashi, N. A1 - Mix, Renate A1 - Unger, Wolfgang T1 - Depth Resolved Chemical Characterization of Plasma Polymers by Energy Resolved XPS T2 - 13th European Conference on Applications of Surface and Interface Analysis CY - Antalya, Turkey DA - 2009-10-18 PY - 2009 AN - OPUS4-19763 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Girard-Lauriault, Pierre-Luc A1 - Illgen, René A1 - Ruiz, J.-C. A1 - Wertheimer, M. R. A1 - Unger, Wolfgang T1 - Functionalization of graphite and carbon nanotube surfaces by vacuum-ultraviolet induced photochemical processes T2 - ECASIA '11 - 14th European Conference on Applications of surface and Interface Analysis CY - Cardiff, Wales DA - 2011-09-04 PY - 2011 AN - OPUS4-24203 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Girard-Lauriault, Pierre-Luc A1 - Dietrich, Paul A1 - Gross, Thomas A1 - Unger, Wolfgang T1 - Is quantitative chemical derivatization XPS of plasma deposited organic coatings a valid analytical procedure? N2 - Functionalized organic layers prepared by plasma processes have complex surface chemistries. The problem of elucidating such chemistries is an extensively studied subject. One of the preponderant methods used to acquire information on specific functional groups is chemical derivatization XPS. In this communication, we focus on rather popular chemical derivatization XPS approaches, for instance, the quantification of amines with 4-trifluoromethyl benzaldehyde and of hydroxyl groups with trifluoroacetic anhydride. Although these procedures have been used for a long period by various laboratories, the use of varying protocols is obvious. Comparison of results is therefore difficult. We discuss steps toward a valid experimental procedure, in particular, the calculation of concentrations, the preparation of test samples, the pitfalls, and the shortcomings. KW - Organic coatings KW - Amine KW - Alcohol KW - Chemical derivatization KW - XPS PY - 2012 U6 - https://doi.org/10.1002/sia.4947 SN - 0142-2421 SN - 1096-9918 VL - 44 IS - 8 SP - 1135 EP - 1140 PB - Wiley CY - Chichester AN - OPUS4-26234 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dietrich, Paul A1 - Horlacher, T. A1 - Girard-Lauriault, Pierre-Luc A1 - Gross, Thomas A1 - Lippitz, Andreas A1 - Min, Hyegeun A1 - Wirth, Thomas A1 - Castelli, R. A1 - Seeberger, P. A1 - Unger, Wolfgang T1 - Multimethod chemical characterization of carbohydrate-functionalized surfaces N2 - A combined XPS, NEXAFS, and ToF-SIMS chemical surface characterization of carbohydrate-functionalized gold and glass surfaces is presented. Spot shape and chemical composition across a spot surface are provided by surface-sensitive methods as ToF-SIMS and XPS, used in their imaging modes. Moreover, the feasibility of this multimethod approach to control relevant production steps of a carbohydrate microarray prototype is demonstrated. KW - Carbohydrates KW - Microarrays KW - Self-assembled monolayers KW - XPS KW - NEXAFS KW - ToF-SIMS PY - 2011 U6 - https://doi.org/10.1080/07328303.2011.615181 SN - 0732-8303 VL - 30 IS - 4-6 SP - 361 EP - 372 PB - Taylor & Francis CY - London [u.a.] AN - OPUS4-24874 LA - eng 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 - JOUR 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 sub-surface chemical characterization of air-exposed plasma polymers by energy-resolved XPS KW - Plasma polymers KW - Synchrotron XPS KW - Depth profiling KW - Derivatisation PY - 2010 U6 - https://doi.org/10.1002/ppap.200900130 SN - 1612-8850 SN - 1612-8869 VL - 7 IS - 6 SP - 474 EP - 481 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-21711 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Girard-Lauriault, Pierre-Luc A1 - Lippitz, Andreas A1 - Wertheimer, M. R. A1 - Unger, Wolfgang T1 - Plasma polymer films for biomedical application T2 - Group Seminar of Prof. Dr. Peter Saalfrank, Universität Potsdam CY - Potsdam, Germany DA - 2010-05-26 PY - 2010 AN - OPUS4-21422 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -