TY - JOUR A1 - Dietrich, Paul A1 - Unger, Wolfgang T1 - Charakterisierung von Microarrays durch Anwendung physikalischer Methoden der chemischen Oberflächenanalytik KW - Oberflächenmodifizierungen KW - Self-assemblierende Monolagen KW - Thiole KW - Aminierte Oberflächen KW - Microarrays KW - XPS KW - ToF-SIMS PY - 2010 UR - http://www.analytik-news.de/Fachartikel/Volltext/BAM1.pdf SP - 1 EP - 11 PB - Dr. Beyer Internet-Beratung CY - Ober-Ramstadt AN - OPUS4-21834 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Dietrich, Paul A1 - Graf, Nora A1 - Gross, Thomas A1 - Lippitz, Andreas A1 - Schüpbach, B. A1 - Terfort, A. A1 - Unger, Wolfgang T1 - Characterization of self-assembled monolayers of terphenylthiols with amine head groups KW - Terphenylthiolate SAMs KW - Gold KW - Microarray KW - NEXAFS PY - 2008 SP - 195 EP - 197 AN - OPUS4-22909 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Improved quality of microarray platforms by using combined surface analytical tools (XPS, NEXAFS, ToF-SIMS, Water Contact Angle Goniometry) T2 - 13th European Conference on Applications of Surface and Interface Analysis ECASIA 09 CY - Antalya, Turkey DA - 2009-10-18 PY - 2009 AN - OPUS4-19944 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dietrich, Paul A1 - Graf, Nora A1 - Gross, Thomas A1 - Lippitz, Andreas A1 - Schüpbach, B. A1 - Bashir, A. A1 - Wöll, Ch. A1 - Terfort, A. A1 - Unger, Wolfgang T1 - Self-assembled monolayers of aromatic omega-aminothiols on gold: surface chemistry and reactivity N2 - Amino-terminated self-assembled monolayers on gold substrates were studied by X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine structure (NEXAFS) measurements, and atomic force microscopy (AFM). Two different ω-amino-4,4'-terphenyl substituted alkanethiols of the general structure H2N-(C6H4)3-(CH2)n-SH (ATPn) were used: 2-(4''-amino-1,1':4',1''-terphenyl-4-yl)ethane-1-thiol (n = 2, ATP2) and 3-(4''-amino-1,1':4',1''-terphenyl-4-yl)propane-1-thiol (n = 3, ATP3). Moreover, the addressability of amino groups within the films was investigated by chemical derivatization of ATPn SAMs with 3,5-bis(trifluoromethyl)phenyl isothiocyanate (ITC) forming fluorinated thiourea ATPn-F films. Evaluation of high-resolution C 1s and N 1s XPS data revealed successful derivatization of at least 50% of surface amino species. Furthermore, it could be demonstrated by angle-resolved NEXAFS spectroscopy that chemical derivatization with ITC has no noticeable influence on the preferential upright orientation of the molecules in the SAMs. KW - Gold KW - Self-assembled monolayer KW - Thiols KW - Amino surfaces KW - XPS KW - NEXAFS PY - 2010 DO - https://doi.org/10.1021/la903293b SN - 0743-7463 SN - 1520-5827 VL - 26 IS - 6 SP - 3949 EP - 3954 PB - American Chemical Society CY - Washington, DC AN - OPUS4-20990 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Carbohydrate-functionalized surfaces: Analysis by an multi-method approach T2 - 5th Glycan Forum CY - Berlin, Germany DA - 2011-03-10 PY - 2011 AN - OPUS4-23344 LA - deu 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. 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 DO - 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 - CONF A1 - Dietrich, Paul T1 - Different w-aminothiols and self-assembled monolayers thereof on gold T2 - First Joint Ber II and Bessy II Users Meeting, WISTA Adlershof CY - Berlin, Germany DA - 2009-11-12 PY - 2009 AN - OPUS4-20417 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Surface chemical imaging (ToF - SIMS and XPS) of carbohydrate microarray prototypes T2 - ECASIA'09 - 13th European Conference on Applications of Surface and Interface Analysis CY - Antalya, Turkey DA - 2009-10-18 PY - 2009 AN - OPUS4-20418 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul 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 - JOUR A1 - Voigtsberger, Paul A1 - Conrad, Dietrich T1 - Sicherheitstechnische Untersuchungen an Hydraulikölen und Verdichterschmierstoffen PY - 1965 SN - 0340-9481 IS - 9 SP - 329 EP - 333 PB - Schmidt CY - Berlin AN - OPUS4-10449 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Voigtsberger, Paul A1 - Conrad, Dietrich T1 - Sicherheitstechnische Untersuchungen an Druckzerstäuberdosen PY - 1965 SN - 0003-7788 IS - 11 SP - 304 EP - 311 PB - Kohlhammer CY - Stuttgart AN - OPUS4-10450 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Surface analytical investigations (XPS, NEXAFS and ToF-SIMS) of carbohydrate-functionalized surfaces T2 - SIMS XVIII, 18th International Conference on Secondary Ion Mass Spectrometry CY - Trento, Italy DA - 2011-09-18 PY - 2011 AN - OPUS4-24445 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Surface chemical characterization of carbohydrate films on gold T2 - ECASIA '11 CY - Cardiff, Wales DA - 2011-09-09 PY - 2011 AN - OPUS4-24239 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Epoxy-functionalized Surfaces: Surface chemical analysis and fluorescence labeling of surface species T2 - ECASIA '11 CY - Cardiff, Wales DA - 2011-09-09 PY - 2011 AN - OPUS4-24242 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Surface chemical Analysis of Microarrays: Problems and Perspectives T2 - ECASIA'11 CY - Cardiff, Wales DA - 2011-09-09 PY - 2011 AN - OPUS4-24243 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Entwicklung einer normativen analytischen Infrastruktur für die Qualitätssicherung von Mikroarrays T2 - 3. Berlin-Brandenburger Technologieforum In Vitro-Diagnostik und Bioanalytik CY - Potsdam, Germany DA - 2011-06-09 PY - 2011 AN - OPUS4-23965 LA - deu 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 DO - 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 - Dietrich, Paul T1 - Microarrays - Surface Chemical Characterization T2 - Functional Genomics and Proteomics - Applications, Molecular Diagnostics & Next Generation Sequencing CY - Frankfurt am Main, Germany DA - 2012-02-02 PY - 2012 AN - OPUS4-25529 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Carbohydrate-functionalized surfaces: Analysis by a multi-method approach T2 - 6. Senftenberger Innovationsforum: Multiparameteranalytik mit zellulären Assays CY - Senftenberg, Germany DA - 2012-03-16 PY - 2012 AN - OPUS4-25683 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Epoxy-functionalized Surfaces: Surface chemical analysis and fluorescence labeling of surface species T2 - 6. Senftenberger Innovationsforum: Multiparameteranalytik mit zellulären Assays CY - Senftenberg, Germany DA - 2012-03-16 PY - 2012 AN - OPUS4-25684 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - How successful is surface chemical analysis in the characterization of (model) diagnostic devices exploiting probe-target interaction? T2 - 65th IUVSTA Workshop "Measuring molecular adsorption at the solid liquid interface" CY - Peckforton, England DA - 2012-05-14 PY - 2012 AN - OPUS4-25968 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Song, X. A1 - Ma, Y. A1 - Wang, C. A1 - Dietrich, Paul A1 - Unger, Wolfgang A1 - Luo, Y. T1 - Effects of protonation, hydrogen bonding, and photodamaging on X-ray spectroscopy of the amine terminal group in aminothiolate monolayers N2 - The amine headgroup, NH2, in aminothiolate monolayers can often generate unexpectedly rich structures in its N K-edge X-ray photoelectron spectra (XPS) and near-edge X-ray absorption fine structure (NEXAFS) spectra that are difficult to assign. We have carried out density functional theory (DFT) calculations to study the XPS and NEXAFS of amine headgroup in four different aminothiolate monolayers, namely, aliphatic 11-aminoundecane-1-thiol (AUDT), aromatic 4-aminobenzenethiol (ABT), araliphatic 4-aminophenylbutane-1-thiol (APBT), and 3-(4''-amino-1,1':4',1''-terphenyl-4-yl)propane-1-thiol (ATPT), with the focus on structure changes caused by protonation, hydrogen bonding, and X-ray damaging. Spectra of all possible saturated and unsaturated species, as well as X-ray damage products, such as imine, nitrile, azo species, and cumulative double bonds, have been thoroughly examined. It is found that extra spectral structures observed in the experimental XPS spectra do not result from protonation but from the formation of a primary ammonium. The X-ray excitation can induce cross-linking between two neighboring molecules to form different complexes that contribute to the π* features in NEXAFS spectra. KW - Surface analysis KW - Spectrum simulation KW - X-ray absorption spectroscopy KW - Self assembling monolayer PY - 2012 DO - https://doi.org/10.1021/jp302716w SN - 1932-7447 SN - 1089-5639 VL - 116 IS - 23 SP - 12649 EP - 12654 PB - Soc. CY - Washington, DC AN - OPUS4-26255 LA - eng 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 DO - 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 - Funk, C. A1 - Dietrich, Paul A1 - Gross, Thomas A1 - Min, Hyegeun A1 - Unger, Wolfgang A1 - Weigel, W. T1 - Epoxy-functionalized surfaces for microarray applications: surface chemical analysis and fluorescence labeling of surface species N2 - Methods for characterization of epoxy-functionalized substrates used for microarray applications, prepared by silanization with 3-glycidoxypropyltrimethoxysilane, have been developed. Contact angle measurements, X-ray photoelectron spectroscopy, time of flight secondary ion mass spectrometry and fluorescence based methods have been applied to investigate these epoxy-functionalized microarray substrates. The surface density of epoxy-functionalized glass slides was investigated by fluorescence labeling of surface species utilizing Rhodamine 110 as fluorescence probe. KW - Epoxy silane KW - Microarrays KW - Fluorescence KW - XPS KW - ToF-SIMS KW - Surface analysis PY - 2012 DO - https://doi.org/10.1002/sia.3856 SN - 0142-2421 SN - 1096-9918 VL - 44 IS - 8 SP - 890 EP - 894 PB - Wiley CY - Chichester AN - OPUS4-26342 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Surface chemical analysis for the characterization of (bio)interfaces for diagnostic devices T2 - IUVSTA ECM 114 Highlight Seminar CY - Bratislava, Slovakia DA - 2012-10-01 PY - 2012 AN - OPUS4-27157 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Girard-Lauriault, P.-L. A1 - Dietrich, Paul A1 - Gross, Thomas A1 - Wirth, Thomas A1 - Unger, Wolfgang T1 - Chemical characterization of the long-term ageing of nitrogen-rich plasma polymer films under various ambient conditions N2 - Nitrogen rich plasma polymer films (L-PPE:N) were prepared by low-pressure RF plasma using a 1:1 mixture of ethylene and ammonia and aged for 345 d in four different ambient conditions: (i) at room temperature (RT) in air; (ii) at RT in nitrogen; (iii) at -20?°C in air and; (iv) at –20 °C in nitrogen. The films were analyzed by X-ray photoelectron spectroscopy (XPS) and by time-of-flight secondary ion mass spectrometry (ToF-SIMS) at various intervals over the duration of the experiment. The ageing of primary amines, NH2, was followed by chemical derivatization with 4-trifluoromethyl benzaldehyde. Storage at –20 °C, mostly independently of ambient atmosphere, slowed down ageing to almost undetectable levels as evaluated by the analytical methods used for this study. KW - Ageing KW - Plasma polymers KW - Primary amines KW - ToF-SIMS KW - XPS PY - 2013 DO - https://doi.org/10.1002/ppap.201200118 SN - 1612-8850 SN - 1612-8869 VL - 10 IS - 4 SP - 388 EP - 395 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-28006 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Darlatt, Erik A1 - Nefedov, A. A1 - Traulsen, C.H.-H. A1 - Poppenberg, J. A1 - Richter, S. A1 - Dietrich, Paul A1 - Lippitz, Andreas A1 - Illgen, René A1 - Kühn, Julius A1 - Schalley, C.A. A1 - Wöll, Ch. A1 - Unger, Wolfgang T1 - Interperetation of experimental N K NEXAFS of azide, 1,2,3-triazole and terpyridyl groups by DFT spectrum simulations N2 - Experimental N K-edge NEXAFS data of surface immobilized azide, 1,2,3-triazole and terpyridyl groups are interpreted with the help of DFT spectrum simulations. Assignments of π* resonances in experimental N K-edge NEXAFS spectra to nitrogen atoms within these functional groups have been made. The azide was immobilized on gold as the head group of a thiol SAM, 1,2,3-triazole was formed on this SAM by click reaction and terpyridyl groups were introduced as substituents of the acetylene used for the click reaction. For azide-terminated molecules, DFT spectrum simulations are found to be useful to find measurement conditions delivering experimental N K-edge NEXAFS data with negligible X-ray damage. The 1,2,3-triazole group is found to be rather stable under X-ray irradiation. KW - N K-edge NEXAFS KW - XANES KW - Surface click chemistry KW - Density functional theory KW - Azide KW - 1,2,3-Triazole PY - 2012 DO - https://doi.org/10.1016/j.elspec.2012.09.008 SN - 0368-2048 SN - 1873-2526 VL - 185 IS - 12 SP - 621 EP - 624 PB - Elsevier CY - Amsterdam AN - OPUS4-27774 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Oberflächenanalytische Verfahren ur Charakterisierung von Microarrays T2 - Workshop "Qualität und Reproduzierbarkeit von Microarrays CY - Berlin, Germany DA - 2013-06-13 PY - 2013 AN - OPUS4-28797 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - XPS studies of epoxy surfaces used for carbohydrate reference surfaces and arrays T2 - Potsdam Days on Bioanalysis 2013 CY - Potsdam-Golm, Germany DA - 2013-11-07 PY - 2013 AN - OPUS4-29875 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Characterization of lectin carbohydrate interactions by XPS and NEXAFS T2 - ECASIA´13 - 15th European Conference on Applications of Surface and Interface Analysis 2013 CY - Cagliari, Italy DA - 2013-10-13 PY - 2013 AN - OPUS4-29578 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Development of biosensor standard surfaces with carbohydrate probes T2 - 15th European Conference on Applications of Surface and Interface Analysis 2013 - ECASIA 13 CY - Cagliari, Italy DA - 2013-10-13 PY - 2013 AN - OPUS4-30111 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nietzold, Carolin A1 - Dietrich, Paul A1 - Holzweber, M. A1 - Lippitz, Andreas A1 - Kamalakumar, A. A1 - Blanchard, V. A1 - Ivanov-Pankov, S. A1 - Weigel, W. A1 - Panne, Ulrich A1 - Unger, Wolfgang T1 - Surface chemical characterization of model glycan surfaces and shelf life studies of glycan microarrays using XPS, NEXAFS spectroscopy, ToF-SIMS and fluorescence scanning N2 - Biomedical applications, including functional biomaterials, carbohydrate-arrays, and glycan-based biosensors. The chemistry of glycan immobilization plays an essential role in the bioavailability and function of surface bound carbohydrate moieties. For biomedical applications the stability over time (shelf life) of glycan arrays is a crucial factor. Herein we report on approaches for surface and interface characterization relevant to the needs of production of glycan microarrays which were tested using model carbohydrate surfaces. For detailed characterization of glycan model surfaces we used a combination of X-ray photoelectron spectroscopy (XPS), near edge X-ray absorption fine structure spectroscopy (NEXAFS) and ToF SIMS which are complementary techniques of surface chemical analysis. Links to fluorescence spectroscopy often used for characterization in the microarray community were established as well. In detail, amine-reactive silicon oxide and glass surfaces were used for anchoring oligosaccharides with an amino linker. The amount of surface bound carbohydrates was estimated by X-ray photoelectron spectroscopy (XPS). Glycan immobilization was investigated using lectins, which are glycan-binding molecules. A shelf life study of model glycan microarrays on epoxy-coated glass surfaces was done over a period of 160 days under different storage conditions utilizing fluorescence, ToF-SIMS and XPS analysis. It was shown that glycan activity of the models used can be maintained at least for half a year of storage at 4 °C. KW - Glycan microarray KW - XPS KW - NEXAFS KW - ToF-SIMS KW - Fluorescence PY - 2018 UR - https://www.sciencedirect.com/science/article/pii/S0169433218320300?via%3Dihub DO - https://doi.org/10.1016/j.apsusc.2018.07.133 SN - 0169-4332 SN - 1873-5584 VL - 459 SP - 860 EP - 873 PB - Elsevier B.V. AN - OPUS4-46212 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fischer, Tobias A1 - Dietrich, Paul A1 - Streeck, C. A1 - Ray, S. A1 - Nutsch, A. A1 - Shard, A. A1 - Beckhoff, B. A1 - Unger, Wolfgang A1 - Rurack, Knut T1 - Quantification of variable functional-group densities of mixed-silane monolayers on surfaces via a dual-mode fluorescence and XPS label N2 - The preparation of aminated monolayers with a controlled density of functional groups on silica surfaces through a simple vapor deposition process employing different ratios of two suitable monoalkoxysilanes, (3-aminopropyl)diisopropylethoxysilane (APDIPES) and (3-cyanopropyl)dimethylmethoxysilane (CPDMMS), and advances in the reliable quantification of such tailored surfaces are presented here. The one-step codeposition process was carried out with binary silane mixtures, rendering possible the control over a wide range of densities in a single step. In particular, APDIPES constitutes the functional silane and CPDMMS the inert component. The procedure requires only small amounts of silanes, several ratios can be produced in a single batch, the deposition can be carried out within a few hours and a dry atmosphere can easily be employed, limiting self-condensation of the silanes. Characterization of the ratio of silanes actually bound to the surface can then be performed in a facile manner through contact angle measurements using the Cassie equation. The reliable estimation of the number of surface functional groups was approached with a dual-mode BODIPY-type fluorescence label, which allows quantification by fluorescence and XPS on one and the same sample. We found that fluorescence and XPS signals correlate over at least 1 order of magnitude, allowing for a direct linking of quantitative fluorescence analysis to XPS quantification. Employment of synchrotron-based methods (XPS; reference-free total reflection X-ray fluorescence, TXRF) made the traceable quantification of surface functional groups possible, providing an absolute reference for quantitative fluorescence measurements through a traceable measurement chain. KW - Oberflächenanalytik KW - Fluoreszenz KW - XPS KW - TXRF KW - Funktionelle Gruppen PY - 2015 DO - https://doi.org/10.1021/ac503850f SN - 0003-2700 SN - 1520-6882 VL - 87 IS - 5 SP - 2685 EP - 2692 PB - American Chemical Society CY - Washington, DC AN - OPUS4-34470 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nietzold, Carolin A1 - Dietrich, Paul A1 - Lippitz, Andreas A1 - Panne, Ulrich A1 - Unger, Wolfgang T1 - Cyclodextrin – ferrocene host – guest complexes on silicon oxide surfaces N2 - Research on carbohydrate based interactions with proteins, nucleic acids or antibodies has gained increased interest in the last years especially in clinical diagnosis or drug development. The efficiency of diagnostic interfaces depends upon the number of probe molecules, e.g. carbohydrates. The control of surface parameters as density and distribution of immobilized carbohydrates is essential for a reliable interaction with protein analytes. A controlled production of biomolecular interfaces can be reached by a stepwise quality control during buildup of these biointerfaces. Here, ß-amino-cyclodextrin molecules were attached to amine-reactive silicon oxide surfaces via click chemistry to construct a model biosensor surface. The amount of surface bound carbohydrates was determined indirectly after chemical derivatization with 4-(trifluoromethyl)-benzylamine (TFMBA). Moreover, these surfaces were used to form host-guest complexes of ferrocene (guest) and β-cyclodextrin (host) moieties to mimic the target binding (sensing) of the model biosensor. Surface chemical analysis of all steps during biosensor construction was performed using X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure spectroscopy (NEXAFS). Our approach widens the possibilities to generate switchable surfaces based on ß-Cyclodextrin surfaces for biosensor applications. KW - ß-amino-cyclodextrin KW - Ferrocene KW - Guest complexe KW - XPS KW - NEXAFS PY - 2016 DO - https://doi.org/10.1002/sia.5958 SN - 0142-2421 SN - 1096-9918 VL - 48 IS - 7 SP - 606 EP - 610 PB - Wiley AN - OPUS4-36856 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hennig, Andreas A1 - Dietrich, Paul A1 - Hemmann, Felix A1 - Thiele, T. A1 - Borcherding, H. A1 - Hoffmann, Angelika A1 - Schedler, U. A1 - Jäger, Christian A1 - Resch-Genger, Ute A1 - Unger, Wolfgang T1 - En route to traceable reference standards for surface group quantifications by XPS, NMR and fluorescence spectroscopy N2 - The fluorine content of polymer particles labelled with 2,2,2-trifluoroethylamine was reliably quantified with overlapping sensitivity ranges by XPS and solid-state NMR. This provides a first step towards reference materials for the metrological traceability of surface group quantifications. The extension of this concept to fluorescence spectroscopy is illustrated. KW - Polymer beads KW - Poly(acrylic acid)-grafted particles KW - XPS KW - SEM KW - Surface analysis KW - Fluorescent dye labeling KW - NMR PY - 2015 DO - https://doi.org/10.1039/c4an02248c SN - 0003-2654 SN - 1364-5528 VL - 140 IS - 6 SP - 1804 EP - 1808 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-32794 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fischer, Tobias A1 - Dietrich, Paul A1 - Unger, Wolfgang A1 - Rurack, Knut T1 - Multimode surface functional group determination: combining steady-state and time-resolved fluorescence with X‑ray photoelectron spectroscopy and absorption measurements for absolute quantification N2 - The quantitative determination of surface functional groups is approached in a straightforward laboratory-based method with high reliability. The application of a multimode BODIPY-type fluorescence, photometry, and X-ray photoelectron spectroscopy (XPS) label allows estimation of the labeling ratio, i.e., the ratio of functional groups carrying a label after reaction, from the elemental ratios of nitrogen and fluorine. The amount of label on the surface is quantified with UV/vis spectrophotometry based on the molar absorption coefficient as molecular property. The investigated surfaces with varying density are prepared by codeposition of 3-(aminopropyl) triethoxysilane (APTES) and cyanoethyltriethoxysilane (CETES) from vapor. These surfaces show high functional group densities that result in significant fluorescence quenching of surface-bound labels. Since alternative quantification of the label on the surface is available through XPS and photometry, a novel method to quantitatively account for fluorescence quenching based on fluorescence lifetime (τ) measurements is shown. Due to the complex distribution of τ on high-density surfaces, the stretched exponential (or Kohlrausch) function is required to determine representative mean lifetimes. The approach is extended to a commercial Rhodamine B isothiocyanate (RITC) label, clearly revealing the problems that arise from such charged labels used in conjunction with silane surfaces. KW - surface group quantification KW - fluorescence spectroscopy KW - absorption spectroscopy KW - X-ray photoelectron spectroscopy KW - dyes PY - 2016 DO - https://doi.org/DOI: 10.1021/acs.analchem.5b03468 SN - 0003-2700 VL - 88 IS - 2 SP - 1210 EP - 1217 PB - American Chemical Society CY - Washington, DC AN - OPUS4-35832 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hecht, Mandy A1 - Fischer, Tobias A1 - Dietrich, Paul A1 - Kraus, Werner A1 - Descalzo López, Ana Belén A1 - Unger, Wolfgang A1 - Rurack, Knut T1 - Fluorinated Boron-Dipyrromethene (BODIPY) dyes: bright and versatile probes for surface analysis N2 - A family of bright boron-dipyrromethene-type fluorophores with a high number of fluorine atoms (F-BODIPYs) has been developed and characterized by X-ray crystallography and optical spectroscopy. The introduction of 3,5-bis(trifluoromethyl)phenyl and pentafluorophenyl moieties significantly enhances the photostability of such dyes, yielding for instance photostable near-infrared (NIR) fluorophores that show emission maxima>750 nm, when the BODIPY's π system is extended with two (dimethylamino)styryl and (dimethylamino)naphthastyryl moieties, or green-emitting BODIPYs with fluorescence quantum yields of unity. When equipped with a suitable group that selectively reacts for instance with amines, F-BODIPYs can be used as potent dual labels for the quantification of primary amino groups on surfaces by X-ray photoelectron spectroscopy (XPS) and fluorescence, two powerful yet complementary tools for the analysis of organic surface functional groups. The advantage of reactive F-BODIPYs is that they allow a fast and non-destructive mapping of the labelled supports with conventional fluorescence scanners and a subsequent quantification of selected areas of the same sample by the potentially traceable XPS technique. The performance is exemplarily shown here for the assessment of the amino group density on SiO2 supports, one of the most common reactive silica supports, in particular, for standard microarray applications. KW - Amino groups KW - Dyes KW - Fluorescence KW - Surface analysis KW - X-ray photoelectron spectroscopy KW - Amino-Gruppen KW - Farbstoffe KW - Fluoreszenz KW - Oberflächenanalytik KW - Röntgen-Photoelektronen-Spektroskopie PY - 2013 DO - https://doi.org/10.1002/open.201200039 SN - 2191-1363 VL - 2 IS - 1 SP - 25 EP - 38 PB - Wiley-VCH-Verl. CY - Weinheim AN - OPUS4-27783 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dietrich, Paul T1 - Optimization of carbohydrate microarray performances T2 - Bunsentagung 2010 "Interfacial Systems Chemistry: Out of the Vacuumm, Through the Liquid, Into the Cell" CY - Bielefeld, Germany DA - 2010-05-13 PY - 2010 AN - OPUS4-21366 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dietrich, Paul A1 - Hennig, Andreas A1 - Holzweber, Markus A1 - Thiele, T. A1 - Borcherding, H. A1 - Lippitz, Andreas A1 - Schedler, U. A1 - Resch-Genger, Ute A1 - Unger, Wolfgang T1 - Surface analytical study of poly(acrylic acid)-grafted microparticles (beads): characterization, chemical derivatization, and quantification of surface carboxyl groups N2 - We report a surface analytical study of poly(methyl methacrylate) (PMMA) microparticles (beads) with a grafted shell of poly(acrylic acid) (PAA) with thicknesses up to 4 nm using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and near-edge X-ray adsorption fine structure (NEXAFS) spectroscopy. These polymer microparticles were analyzed before and after reaction of the surface carboxyl (CO2H) groups with 2,2,2-trifluoroethylamine (TFEA) to gain a better understanding of methods with use of covalently bound probe molecules for surface group analysis. The results obtained with chemical derivatization XPS using TFEA are discussed in terms of surface quantification of reactive CO2H groups on these PAA-coated microparticles. A labeling yield of about 50% was found for TFEA-derivatized particles with amounts of surface-grafted CO2H groups of 99 µmol/g or more, which is consistent with predicted reaction yields for homogeneously dispersed PAA hydrogels. KW - Polymer microparticles KW - Poly(acrylic acid)-grafted microparticles KW - Beads KW - XPS KW - SEM KW - NEXAFS KW - Surface analysis KW - Fluorine labeling PY - 2014 DO - https://doi.org/10.1021/jp505519g SN - 1932-7447 SN - 1089-5639 VL - 118 IS - 35 SP - 20393 EP - 20404 PB - Soc. CY - Washington, DC AN - OPUS4-31326 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Swaraj, S. A1 - Dietrich, Paul A1 - Unger, Wolfgang T1 - Simultaneous surface and bulk sensitive XAS measurements of magnetic particle clusters N2 - Magnetic iron oxide nanoparticle clusters (mnpc) coated with organic stabilizers were investigated using scanning transmission x-ray microscopy (STXM). Simultaneous surface and bulk sensitive Fe L₃ edge absorption spectra, obtained using a photomultiplier tube and a channeltron, were used to detect subtle changes in the oxidation state in the surface and bulk of Iron Oxide mnpc. The effectiveness of this mode of STXM operation is demonstrated for these nanoparticle clusters. T2 - X-Ray Microscopy Conference 2016 (XRM 2016) CY - Oxford, UK DA - 15.08. 2016 KW - Fe L3 edge absorption spectra KW - Scanning transmission x- ray microscopy KW - Magnetic iron oxide nanoparticle clusters KW - XAS PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-410576 UR - http://iopscience.iop.org/article/10.1088/1742-6596/849/1/012014/pdf DO - https://doi.org/10.1088/1742-6596/849/1/012014 SN - 1742-6588 VL - 849 SP - 012014, 1 EP - 012014, 5 PB - IOP Publishing AN - OPUS4-41057 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 DO - 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 - Belsey, N. A. A1 - Cant, D. J. H. A1 - Minelli, C. A1 - Araujo, J. R. A1 - Bock, B. A1 - Brüner, P. A1 - Castner, D. G. A1 - Ceccone, G. A1 - Counsell, J. D. P. A1 - Dietrich, Paul M. A1 - Engelhardt, M. H. A1 - Fearn, S. A1 - Galhardo, C. E. A1 - Kalbe, H. A1 - Kim, J. W. A1 - Lartundo-Rojas, L. A1 - Luftman, H. S. A1 - Nunney, T. S. A1 - Pseiner, J. A1 - Smith, E. F. A1 - Spampinato, V. A1 - Sturm, J. M. A1 - Thomas, A. G. A1 - Treacy, J. P. W. A1 - Veith, L. A1 - Wagstaffe, M. A1 - Wang, H. A1 - Wang, M. A1 - Wang, Y.-C. A1 - Werner, W. A1 - Yang, L. A1 - Shard, A. G. T1 - Versailles Project on Advanced Materials and Standards Interlaboratory Study on Measuring the Thickness and Chemistry of Nanoparticle Coatings Using XPS and LEIS N2 - We report the results of a Versailles Project on Advanced Materials and Standards (VAMAS) interlaboratory study on the measurement of the shell thickness and chemistry of nanoparticle coatings. Peptide-coated gold particles were supplied to laboratories in two forms: a colloidal suspension in pure water and particles dried onto a silicon wafer. Participants prepared and analyzed these samples using either X-ray photoelectron spectroscopy (XPS) or low energy ion scattering (LEIS). Careful data analysis revealed some significant sources of discrepancy, particularly for XPS. Degradation during transportation, storage, or sample preparation resulted in a variability in thickness of 53%. The calculation method chosen by XPS participants contributed a variability of 67%. However, variability of 12% was achieved for the samples deposited using a single method and by choosing photoelectron peaks that were not adversely affected by instrumental transmission effects. The study identified a need for more consistency in instrumental transmission functions and relative sensitivity factors since this contributed a variability of 33%. The results from the LEIS participants were more consistent, with variability of less than 10% in thickness, and this is mostly due to a common method of data analysis. The calculation was performed using a model developed for uniform, flat films, and some participants employed a correction factor to account for the sample geometry, which appears warranted based upon a simulation of LEIS data from one of the participants and comparison to the XPS results. KW - VAMAS KW - Interlaboratory Study KW - Nanoparticle coating KW - XPS KW - LEIS KW - shell thicknss and chemistry PY - 2016 UR - http://pubs.acs.org/doi/pdf/10.1021/acs.jpcc.6b06713 DO - https://doi.org/10.1021/acs.jpcc.6b06713 IS - 120 SP - 24070 EP - 24079 PB - ACS Publications AN - OPUS4-38428 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dietrich, Paul M. A1 - Lange, Nele A1 - Lippitz, Andreas A1 - Holzweber, Markus A1 - Kulak, N. A1 - Unger, Wolfgang T1 - Click chemistry on silicon nitride for biosensor fabrication N2 - Biosensors are of essential importance in medical and biological diagnostics. Often, they are produced using silane chemistry on glass or silicon oxide surfaces. However, controlling that silane chemistry is challenging. Here, we present an alternative strategy to form functional organic layers and biosensors on silicon Nitride (Si3N4). H-terminated Si3N4 films are used to generate reactive azide groups by various azidation methods. Biomolecular probes can then be immobilized using click chemistry reactions with the azide groups and due to its high sensitivity in XPS a fluorine-substituted test alkyne was utilized to optimize click chemistry conditions. After that a biotinylated alkyne was clicked to Si3N4 surfaces followed by immobilization of streptavidin as analyte in a model assay. The functionalized surfaces were thoroughly characterized by surface chemical analysis using X-ray photoelectron spectroscopy (XPS) and near edge X-ray absorption fine structure (NEXAFS)spectroscopy. KW - Biosensors KW - H-terminated Si3N4 films KW - Click chemistry KW - X-ray photoelectron spectroscopy KW - Near edge X-ray absorption fine structure KW - Streptavidin binding PY - 2019 DO - https://doi.org/10.1016/j.apsusc.2019.03.002 SN - 0169-4332 VL - 481 SP - 10 EP - 15 PB - Elsevier B.V. AN - OPUS4-48634 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Swaraj, S. A1 - Dietrich, Paul A1 - Unger, Wolfgang T1 - Simultaneous surface and bulk sensitive XAS measurements of magnetic particle clusters N2 - Magnetic iron oxide nanoparticle clusters (mnpc) coated with organic stabilizers were investigated using scanning transmission x-ray microscopy (STXM). Simultaneous surface and bulk sensitive Fe L3 edge absorption spectra, obtained using a photomultiplier tube and a channeltron, were used to detect subtle changes in the oxidation state in the surface and bulk of Iron Oxide mnpc. The effectiveness of this mode of STXM operation is demonstrated for These nanoparticle clusters. T2 - X-Ray Microscopy Conference 2016 (XRM 2016) CY - Oxford, UK DA - 15.08.2016 KW - Scanning transmission x-ray microscopy (STXM) KW - Magnetic nanoparticles KW - Fe L3 edge absorption spectra PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-435907 UR - http://iopscience.iop.org/article/10.1088/1742-6596/849/1/012014/meta DO - https://doi.org/10.1088/1742-6596/849/1/012014 VL - 849 SP - 012014, 1 EP - 012014, 4 PB - IOP Publishing AN - OPUS4-43590 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heinrich, Thomas A1 - Traulsen, Christoph Hans-Henning A1 - Darlatt, Erik A1 - Richter, S. A1 - Poppenberg, J. A1 - Traulsen, N.L. A1 - Linder, I. A1 - Lippitz, Andreas A1 - Dietrich, Paul A1 - Dib, B. A1 - Unger, Wolfgang A1 - Schalley, C.A. T1 - The versatility of 'Click' reactions at surfaces: Molecular recognition at interfaces N2 - In order to investigate molecular recognition on surfaces, an azide-functionalized monolayer was deposited on gold. The monolayer was characterized by X-ray photoelectron spectroscopy (XPS) and angle-resolved near-edge X-ray absorption fine structure (NEXAFS) experiments and the decomposition of the azide upon irradiation with X-ray beams was investigated. Subsequently, various alkyne-functionalized host and guest molecules were attached to the azide by 1,3-dipolar cycloaddition. These modified surfaces and their host–guest chemistry were analysed by XPS and angle-resolved NEXAFS. The reversibility of guest binding was shown for one example as a proof of principle. KW - 'Click' reaction KW - Azide-terminated surfaces KW - SAMs KW - Host guest molecules KW - Molecular recognition at interfaces PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-306463 DO - https://doi.org/10.1039/C4RA01730G SN - 2046-2069 VL - 4 IS - 34 SP - 17694 EP - 17702 PB - RSC Publishing CY - London AN - OPUS4-30646 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hallier, Dorothea C. A1 - Radnik, Jörg A1 - Dietrich, Paul M. A1 - Seitz, Harald A1 - Hahn, Marc Benjamin T1 - Radiation damage to amino acids, peptides and DNA-binding proteins: the influence of water directly monitored by X-ray photoelectron spectroscopy N2 - Ionizing radiation damage to biomolecules plays a crucial role in radiotherapy as a cancer treatment. Among these, DNA-binding proteins are of particular interest due to their pivotal roles in shielding DNA and facilitating its repair. Hence, in this study, we present first-ever recorded data of radiation damage to a protein monitored directly with near-ambient pressure (NAP) X-ray photoelectron spectroscopy (XPS) under a water atmosphere. This surface sensitive technique was used to in situ damage and probe gene-V protein (G5P, a model DNA-binding protein) under wet NAP conditions and dry vacuum (UHV) conditions to determine the effect of water on the radiation response. In addition, the X-ray radiation damage to selected pure amino acids and short homopeptides was determined to better understand the variety of damage mechanisms within the complex protein. In dry samples, drastic chemical changes were detected in all biomolecules dominated by fragmentation processes. Here, the breakage of peptide bonds in the peptides and the protein are dominant. Surprisingly, hydration – despite introducing additional indirect damage pathways via water radiolysis – led to a reduction in overall radiation damage. This behaviour was attributed to hydration-dependent changes in reaction rates and respective deexcitation and damaging channels within the molecules and secondary species such as low-energy (LEE), (pre)-hydrated/(pre)-solvated electrons and radical species such as hydroxyl radicals. KW - Radiation damage KW - (Near-ambient pressure) X-ray photoelectron spectroscopy KW - Ultra-high vacuum PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-647565 DO - https://doi.org/10.1039/d5cp01887k VL - 27 IS - 48 SP - 1 EP - 22 PB - Royal Society of Chemistry AN - OPUS4-64756 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -