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Gröger R, Heiler T, Schimmel T, Walheim S. Tip-Induced Nanopatterning of Ultrathin Polymer Brushes. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023:e2204962. [PMID: 37026430 DOI: 10.1002/smll.202204962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 02/02/2023] [Indexed: 06/19/2023]
Abstract
Patterned, ultra-thin surface layers can serve as templates for positioning nanoparticlesor targeted self-assembly of molecular structures, for example, block-copolymers. This work investigates the high-resolution, atomic force microscopebased patterning of 2 nm thick vinyl-terminated polystyrene brush layers and evaluates the line broadening due to tip degradation. This work compares the patterning properties with those of a silane-based fluorinated self-assembled monolayer (SAM), using molecular heteropatterns generated by modified polymer blend lithography (brush/SAM-PBL). Stable line widths of 20 nm (FWHM) over lengths of over 20000 µm indicate greatly reduced tip wear, compared to expectations on uncoated SiOx surfaces. The polymer brush acts as a molecularly thin lubricating layer, thus enabling a 5000 fold increase in tip lifetime, and the brush is bonded weakly enough that it can be removed with surgical accuracy. On traditionally used SAMs, either the tip wear is very high or the molecules are not completely removed. Polymer Phase Amplified Brush Editing is presented, which uses directed self-assembly to amplify the aspect ratio of the molecular structures by a factor of 4. The structures thus amplified allow transfer into silicon/metal heterostructures, fabricating 30 nm deep, all-silicon diffraction gratings that could withstand focused high-power 405 nm laser irradiation.
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Affiliation(s)
- Roland Gröger
- Institute of Applied Physics (APH), Karlsruhe Institute of Technology, Wolfgang-Gaede-Str. 1, D-76131, Karlsruhe, Germany
- Center for Single-Atom Technologies (C.SAT), Karlsruhe Institute of Technology, Strasse am Forum 7, D-76131, Karlsruhe, Germany
| | - Tobias Heiler
- Institute of Applied Physics (APH), Karlsruhe Institute of Technology, Wolfgang-Gaede-Str. 1, D-76131, Karlsruhe, Germany
| | - Thomas Schimmel
- Institute of Applied Physics (APH), Karlsruhe Institute of Technology, Wolfgang-Gaede-Str. 1, D-76131, Karlsruhe, Germany
- Center for Single-Atom Technologies (C.SAT), Karlsruhe Institute of Technology, Strasse am Forum 7, D-76131, Karlsruhe, Germany
- Institute of Nanotechnology (INT) and Karlsruhe Nano Micro Facility (KNMFi), Karlsruhe Institute of Technology, Herrmann-von-Helmholtz-Platz 1, D-76344, Eggenstein-Leopoldshafen, Germany
- Materials Research Center for Energy Systems (MZE), Karlsruhe Institute of Technology, Strasse am Forum 7, D-76131, Karlsruhe, Germany
| | - Stefan Walheim
- Institute of Applied Physics (APH), Karlsruhe Institute of Technology, Wolfgang-Gaede-Str. 1, D-76131, Karlsruhe, Germany
- Center for Single-Atom Technologies (C.SAT), Karlsruhe Institute of Technology, Strasse am Forum 7, D-76131, Karlsruhe, Germany
- Institute of Nanotechnology (INT) and Karlsruhe Nano Micro Facility (KNMFi), Karlsruhe Institute of Technology, Herrmann-von-Helmholtz-Platz 1, D-76344, Eggenstein-Leopoldshafen, Germany
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Schade M, Franzka S, Hartmann N. Laser-Induced Functionalization of Organo/Carbon Interfaces for Selective Adsorption of Au Nanoparticles in Microsized Domains. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:8686-8692. [PMID: 28427263 DOI: 10.1021/acs.langmuir.7b00695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Laser microprocessing of highly oriented pyrolytic graphite (HOPG) in conjunction with chemical functionalization routines is used to fabricate functional microsized domains. Infrared and Auger electron spectroscopy, contact angle measurements, and electron microscopy are used for characterization of laser-fabricated structures. HOPG samples are coated with alkylsiloxane monolayers. Laser-induced bromination of coated HOPG samples in gaseous bromine is carried out using a microfocused laser beam at a wavelength of 514 nm and 1/e2 laser spot diameter of about 2 μm. Subsequent azidation and amination results in functional domains with sizes in the range of 1.2 to 40 μm and more. At low laser powers and irradiation times fully functionalized circular-shaped structures are formed. At high laser powers and irradiation times laser processing results in decomposition of the organic monolayer and substrate in the center of the structures yielding donut-shaped structures. After laser processing and chemical transformation Au nanoparticles are selectively adsorbed onto the functional domains. This provides an opportunity to build up functional nanoparticle microarrays on carbon-based materials, e.g., for applications in sensing and electrocatalysis.
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Affiliation(s)
- Martin Schade
- Fakultät für Chemie, Universität Duisburg-Essen , 45117 Essen, Germany
| | | | - Nils Hartmann
- Fakultät für Chemie, Universität Duisburg-Essen , 45117 Essen, Germany
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Stärk M, Schlickeiser F, Nissen D, Hebler B, Graus P, Hinzke D, Scheer E, Leiderer P, Fonin M, Albrecht M, Nowak U, Boneberg J. Controlling the magnetic structure of Co/Pd thin films by direct laser interference patterning. NANOTECHNOLOGY 2015; 26:205302. [PMID: 25927344 DOI: 10.1088/0957-4484/26/20/205302] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Nanosecond pulsed two-beam laser interference is used to generate two-dimensional temperature patterns on a magnetic thin film sample. We show that the original domain structure of a [Co/Pd] multilayer thin film changes drastically upon exceeding the Curie temperature by thermal demagnetization. At even higher temperatures the multilayer system is irreversibly changed. In this area no out-of-plane magnetization can be found before and after a subsequent ac-demagnetization. These findings are supported by numerical simulations using the Landau-Lifshitz-Bloch formalism which shows the importance of defect sites and anisotropy changes to model the experiments. Thus, a one-dimensional temperature pattern can be transferred into a magnetic stripe pattern. In this way one can produce magnetic nanowire arrays with lateral dimensions of the order of 100 nm. Typical patterned areas are in the range of several square millimeters. Hence, the parallel direct laser interference patterning method of magnetic thin films is an attractive alternative to the conventional serial electron beam writing of magnetic nanostructures.
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Affiliation(s)
- Martin Stärk
- Department of Physics, University of Konstanz, Konstanz, Germany
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Schröter A, Franzka S, Hartmann N. Photothermal laser fabrication of micro- and nanostructured chemical templates for directed protein immobilization. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:14841-14848. [PMID: 25397891 DOI: 10.1021/la503814n] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Photothermal patterning of poly(ethylene glycol) terminated organic monolayers on surface-oxidized silicon substrates is carried out using a microfocused beam of a CW laser operated at a wavelength of 532 nm. Trichlorosilane and trimethoxysilane precursors are used for coating. Monolayers from trimethoxysilane precursors show negligible unspecific protein adsorption in the background, i.e., provide platforms of superior protein repellency. Laser patterning results in decomposition of the monolayers and yields chemical templates for directed immobilization of proteins at predefined positions. Characterization is carried out via complementary analytical methods including fluorescence microscopy, atomic force microscopy, and scanning electron microscopy. Appropriate labeling techniques (fluorescent markers and gold clusters) and substrates (native and thermally oxidized silicon substrates) are chosen in order to facilitate identification of protein adsorption and ensure high sensitivity and selectivity. Variation of the laser parameters at a 1/e(2) spot diameter of 2.8 μm allows for fabrication of protein binding domains with diameters on the micrometer and nanometer length scale. Minimum domain sizes are about 300 nm. In addition to unspecific protein adsorption on as-patterned monolayers, biotin-streptavidin coupling chemistry is exploited for specific protein binding. This approach represents a novel facile laser-based means for fabrication of protein micro- and nanopatterns. The routine is readily applicable to femtosecond laser processing of glass substrates for the fabrication of transparent templates.
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Affiliation(s)
- Anja Schröter
- Fakultät für Chemie, Universität Duisburg-Essen , 45117 Essen, Germany
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Nanostructured material surfaces--preparation, effect on cellular behavior, and potential biomedical applications: a review. Int J Artif Organs 2012; 34:963-85. [PMID: 22161281 DOI: 10.5301/ijao.5000012] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/30/2011] [Indexed: 12/14/2022]
Abstract
Nanostructures play important roles in vivo, where nanoscaled features of extracellular matrix (ECM) components influence cell behavior and resultant tissue formation. This review summarizes some of the recent developments in fostering new concepts and approaches to nanofabrication, such as top-down and bottom-up and combinations of the two. As in vitro investigations demonstrate that man-made nanotopography can be used to control cell reactions to a material surface, its potential application in implant design and tissue engineering becomes increasingly evident. Therefore, we present recent progress in directing cell fate in the field of cell mechanics, which has grown rapidly over the last few years, and in various tissue-engineering applications. The main focus is on the initial responses of cells to nanostructured surfaces and subsequent influences on cellular functions. Specific examples are also given to illustrate the potential nanostructures may have for biomedical applications and regenerative medicine.
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Schröter A, Kalus M, Hartmann N. Substrate-mediated effects in photothermal patterning of alkanethiol self-assembled monolayers with microfocused continuous-wave lasers. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2012; 3:65-74. [PMID: 22428098 PMCID: PMC3304314 DOI: 10.3762/bjnano.3.8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Accepted: 01/03/2012] [Indexed: 05/31/2023]
Abstract
In recent years, self-assembled monolayers (SAMs) have been demonstrated to provide promising new approaches to nonlinear laser processing. Most notably, because of their ultrathin nature, indirect excitation mechanisms can be exploited in order to fabricate subwavelength structures. In photothermal processing, for example, microfocused lasers are used to locally heat the substrate surface and initiate desorption or decomposition of the coating. Because of the strongly temperature-dependent desorption kinetics, the overall process is highly nonlinear in the applied laser power. For this reason, subwavelength patterning is feasible employing ordinary continuous-wave lasers. The lateral resolution, generally, depends on both the type of the organic monolayer and the nature of the substrate. In previous studies we reported on photothermal patterning of distinct types of SAMs on Si supports. In this contribution, a systematic study on the impact of the substrate is presented. Alkanethiol SAMs on Au-coated glass and silicon substrates were patterned by using a microfocused laser beam at a wavelength of 532 nm. Temperature calculations and thermokinetic simulations were carried out in order to clarify the processes that determine the performance of the patterning technique. Because of the strongly temperature-dependent thermal conductivity of Si, surface-temperature profiles on Au/Si substrates are very narrow ensuring a particularly high lateral resolution. At a 1/e spot diameter of 2 µm, fabrication of subwavelength structures with diameters of 300-400 nm is feasible. Rapid heat dissipation, though, requires high laser powers. In contrast, patterning of SAMs on Au/glass substrates is strongly affected by the largely distinct heat conduction within the Au film and in the glass support. This results in broad surface temperature profiles. Hence, minimum structure sizes are larger when compared with respective values on Au/Si substrates. The required laser powers, though, are more than one order of magnitude lower. Also, the laser power needed for patterning decreases with decreasing Au layer thickness. These results demonstrate the impact of the substrate on the overall patterning process and provide new perspectives in photothermal laser patterning of ultrathin organic coatings.
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Affiliation(s)
- Anja Schröter
- Fakultät für Chemie, Universität Duisburg-Essen, 45117 Essen, Germany
- Center for Nanointegration Duisburg-Essen (CENIDE), Universität Duisburg-Essen, 47048 Duisburg, Germany
| | - Mark Kalus
- Fakultät für Chemie, Universität Duisburg-Essen, 45117 Essen, Germany
- Center for Nanointegration Duisburg-Essen (CENIDE), Universität Duisburg-Essen, 47048 Duisburg, Germany
| | - Nils Hartmann
- Fakultät für Chemie, Universität Duisburg-Essen, 45117 Essen, Germany
- Center for Nanointegration Duisburg-Essen (CENIDE), Universität Duisburg-Essen, 47048 Duisburg, Germany
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Huber J, Scheinhardt B, Geldhauser T, Boneberg J, Mecking S. Polymerization Catalyst Laser-Interference Patterning. Angew Chem Int Ed Engl 2011; 50:9665-7. [DOI: 10.1002/anie.201103990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Indexed: 11/08/2022]
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8
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Huber J, Scheinhardt B, Geldhauser T, Boneberg J, Mecking S. Polymerization Catalyst Laser-Interference Patterning. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201103990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Tizazu G, El-Zubir O, Brueck SRJ, Lidzey DG, Leggett GJ, Lopez GP. Large area nanopatterning of alkylphosphonate self-assembled monolayers on titanium oxide surfaces by interferometric lithography. NANOSCALE 2011; 3:2511-2516. [PMID: 21431199 DOI: 10.1039/c0nr00994f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We demonstrate that interferometric lithography offers a fast, simple route to nanostructured self-assembled monolayers of alkylphosphonates on the native oxide of titanium. Exposure at 244 nm using a Lloyd's mirror interferometer caused the spatially periodic photocatalytic degradation of the adsorbates, yielding nanopatterns that extended over square centimetre areas. Exposed regions were re-functionalised by a second, contrasting alkylphosphonate, and the resulting patterns were used as templates for the assembly of molecular nanostructures; we demonstrate the fabrication of lines of polymer nanoparticles 46 nm wide. Nanopatterned monolayers were also employed as resists for etching of the metal film. Wires were formed with widths that could be varied between 46 and 126 nm simply by changing the exposure time. Square arrays of Ti dots as small as 35 nm (λ/7) were fabricated using two orthogonal exposures followed by wet etching.
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Affiliation(s)
- Getachew Tizazu
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield, S3 7HF, UK
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Sysoiev D, Fedoseev A, Kim Y, Exner TE, Boneberg J, Huhn T, Leiderer P, Scheer E, Groth U, Steiner UE. Synthesis and Photoswitching Studies of Difurylperfluorocyclopentenes with Extended π-Systems. Chemistry 2011; 17:6663-72. [DOI: 10.1002/chem.201003716] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Indexed: 11/07/2022]
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Xia D, Ku Z, Lee SC, Brueck SRJ. Nanostructures and functional materials fabricated by interferometric lithography. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2011; 23:147-79. [PMID: 20976672 DOI: 10.1002/adma.201001856] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Interferometric lithography (IL) is a powerful technique for the definition of large-area, nanometer-scale, periodically patterned structures. Patterns are recorded in a light-sensitive medium, such as a photoresist, that responds nonlinearly to the intensity distribution associated with the interference of two or more coherent beams of light. The photoresist patterns produced with IL are a platform for further fabrication of nanostructures and growth of functional materials and are building blocks for devices. This article provides a brief review of IL technologies and focuses on various applications for nanostructures and functional materials based on IL including directed self-assembly of colloidal nanoparticles, nanophotonics, semiconductor materials growth, and nanofluidic devices. Perspectives on future directions for IL and emerging applications in other fields are presented.
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Affiliation(s)
- Deying Xia
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
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Scheres L, Klingebiel B, ter Maat J, Giesbers M, de Jong H, Hartmann N, Zuilhof H. Micro- and nanopatterning of functional organic monolayers on oxide-free silicon by laser-induced photothermal desorption. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2010; 6:1918-1926. [PMID: 20677184 DOI: 10.1002/smll.201000189] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The photothermal laser patterning of functional organic monolayers, prepared on oxide-free hydrogen-terminated silicon, and subsequent backfilling of the laser-written lines with a second organic monolayer that differs in its terminal functionality, is described. Since the thermal monolayer decomposition process is highly nonlinear in the applied laser power density, subwavelength patterning of the organic monolayers is feasible. After photothermal laser patterning of hexadecenyl monolayers, the lines freed up by the laser are backfilled with functional acid fluoride monolayers. Coupling of cysteamine to the acid fluoride groups and subsequent attachment of Au nanoparticles allows easy characterization of the functional lines by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Depending on the laser power and writing speed, functional lines with widths between 1.1 μm and 250 nm can be created. In addition, trifluoroethyl-terminated (TFE) monolayers are also patterned. Subsequently, the decomposed lines are backfilled with a nonfunctional hexadecenyl monolayer, the TFE stripes are converted into thiol stripes, and then finally covered with Au nanoparticles. By reducing the lateral distance between the laser lines, Au-nanoparticle stripes with widths close to 100 nm are obtained. Finally, in view of the great potential of this type of monolayer in the field of biosensing, the ease of fabricating biofunctional patterns is demonstrated by covalent binding of fluorescently labeled oligo-DNA to acid-fluoride-backfilled laser lines, which--as shown by fluorescence microscopy--is accessible for hybridization.
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Affiliation(s)
- Luc Scheres
- Laboratory of Organic Chemistry, Wageningen University, Dreijenplein 8, Wageningen 6703 HB, The Netherlands
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Klingebiel B, Scheres L, Franzka S, Zuilhof H, Hartmann N. Photothermal micro- and nanopatterning of organic/silicon interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:6826-31. [PMID: 20095543 DOI: 10.1021/la903926z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Photothermal laser processing of organic monolayers on oxide-free silicon substrates under ambient conditions is investigated. Organic monolayers on Si(100) and Si(111) substrates are prepared via hydrosilylation of H-terminated silicon samples in neat 1-hexadecene and 1-hexadecyne, respectively. Laser processing at lambda = 514 nm and a 1/e(2) spot diameter of 2.6 microm results in local decomposition of the monolayers and oxidation of the exposed substrate. In agreement with the high thermal and chemical stability of these monolayers, a thermokinetic analysis of the data from experiments at distinct laser powers and pulse lengths points to a highly activated process. As a result, processing is strongly nonlinear and allows for subwavelength patterning, with line widths between 0.4 and 1.4 microm. Most remarkably, upon fabrication of dense line patterns, narrow organic monolayer stripes with sharp edges and lateral dimensions of 80 nm are formed. This opens up new perspectives in photothermal engineering of organic/silicon interfaces, e.g., for hybrid microelectronic and sensor applications.
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Geldhauser T, Walheim S, Schimmel T, Leiderer P, Boneberg J. Influence of the Relative Humidity on the Demixing of Polymer Blends on Prepatterned Substrates. Macromolecules 2009. [DOI: 10.1021/ma9022058] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- T. Geldhauser
- University of Konstanz, Universitätsstr. 10, 78457 Konstanz, Germany
| | - S. Walheim
- Institute of Nanotechnology (INT), Forschungszentrum Karlsruhe, D-76021 Karlsruhe, Germany
- Institute of Applied Physics, Center for Functional Nanostructures (CFN), Universität Karlsruhe, D-76128 Karlsruhe, Germany
| | - Th. Schimmel
- Institute of Nanotechnology (INT), Forschungszentrum Karlsruhe, D-76021 Karlsruhe, Germany
- Institute of Applied Physics, Center for Functional Nanostructures (CFN), Universität Karlsruhe, D-76128 Karlsruhe, Germany
| | - P. Leiderer
- University of Konstanz, Universitätsstr. 10, 78457 Konstanz, Germany
| | - J. Boneberg
- University of Konstanz, Universitätsstr. 10, 78457 Konstanz, Germany
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Drexler K, Smirnova J, Galetskaya M, Voss S, Fonin M, Boneberg J, Rüdiger U, Leiderer P, Steiner UE. X-ray photoelectron spectroscopy- and surface plasmon resonance-detected photo release of photolabile protecting groups from nucleoside self-assembled monolayers on gold surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:10794-10801. [PMID: 19603744 DOI: 10.1021/la901346s] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The formation of self-assembled monolayers (SAMs) on gold by 2-(5-iodo-2-nitrophenyl) propoxycarbonyl (I-NPPOC)-protected thymidine with an attached mercaptohexyl succinate linker and the kinetics of photochemical release of the I-NPPOC group were monitored using X-ray photoelectron spectroscopy (XPS) and surface plasmon resonance (SPR) detection. In the XPS spectra, the iodine peaks allowed for specific and accurate monitoring of the presence and loss of I-NPPOC groups on the surface. In the SPR experiment, the overall signal change on photoillumination is in accord with a theoretical estimation of the density of I-NPPOC groups in a dense monolayer. The kinetics roughly follow a biexponential time dependence with two very different time constants, corresponding to photochemical quantum yields of 0.22 and 0.0032, respectively.
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Affiliation(s)
- Katja Drexler
- Department of Chemistry, University of Konstanz, Konstanz, Germany
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