Prof. Girard-Lauriault’s Publications

2012

  • [DOI] Girard-Lauriault, P. L., Illgen, R., Ruiz, J. C., Wertheimer, M. R., & Unger, W. E. S.. (2012). Surface functionalization of graphite and carbon nanotubes by vacuum-ultraviolet photochemical reactions. Applied Surface Science, 258(22), 8448-8454.
    [Bibtex]
    @article{Girard-Lauriault_2012_650,
    Abstract = {Graphite and multiwall carbon nanotube surfaces were functionalized by vacuum-ultraviolet induced photochemistry in NH3 or O-2, in order to introduce amino-(NH2) or hydroxyl (OH) functionalities, respectively. Modified surfaces were characterized by X-ray photoelectron spectroscopy (XPS), which showed significant incorporation of nitrogen (N) and oxygen (O) at the materials' surface. While high-resolution XP spectra did not yield much specific information about the incorporated functional groups, chemical derivatization with 4-trifluoromethyl benzaldehyde and trifluoroacetic anhydride accompanied by XPS enabled quantification of NH2 and OH groups, respectively. Using near edge X-ray absorption fine structure spectroscopy, we assessed the conservation of the aromatic structure following functionalization treatments. (C) 2012 Elsevier B. V. All rights reserved.},
    Author = {Girard-Lauriault, P. L. and Illgen, R. and Ruiz, J. C. and Wertheimer, M. R. and Unger, W. E. S.},
    Doi = {doi:10.1016/j.apsusc.2012.03.012},
    Id = {650},
    Journal = {Applied Surface Science},
    Keywords = {carbon nanotubes graphite vacuum ultraviolet photochemistry surface functionalization amino groups hydroxyl derivatization absorption fine-structure photoelectron-spectroscopy plasma nexafs films nitrogen xps chemistry},
    Number = {22},
    Pages = {8448-8454},
    Title = {Surface functionalization of graphite and carbon nanotubes by vacuum-ultraviolet photochemical reactions},
    Volume = {258},
    Year = {2012},
    Bdsk-Url-1 = {http://dx.doi.org/10.1016/j.apsusc.2012.03.012}}
  • [DOI] Girard-Lauriault, P. L., Gross, T., Lippitz, A., & Unger, W. E. S.. (2012). Chemical and Elemental Depth Profiling of Very Thin Organic Layers by Constant Kinetic Energy XPS: A New Synchrotron XPS Analysis Strategy. Analytical Chemistry, 84(14), 5984-5991.
    [Bibtex]
    @article{Girard-Lauriault_2012_651,
    Abstract = {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, z(95%), 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.},
    Author = {Girard-Lauriault, P. L. and Gross, T. and Lippitz, A. and Unger, W. E. S.},
    Doi = {doi:10.1021/ac300585q},
    Id = {651},
    Journal = {Analytical Chemistry},
    Keywords = {ray photoelectron-spectroscopy angle-resolved xps deposited polymer-films oxygen-plasma biomedical applications atmospheric-pressure nexafs spectroscopy polystyrene surfaces degradation},
    Number = {14},
    Pages = {5984-5991},
    Title = {Chemical and Elemental Depth Profiling of Very Thin Organic Layers by Constant Kinetic Energy XPS: A New Synchrotron XPS Analysis Strategy},
    Volume = {84},
    Year = {2012},
    Bdsk-Url-1 = {http://dx.doi.org/10.1021/ac300585q}}
  • [DOI] Min, H., Girard-Lauriault, P. L., Gross, T., Lippitz, A., Dietrich, P., & Unger, W. E. S.. (2012). Ambient-ageing processes in amine self-assembled monolayers on microarray slides as studied by ToF-SIMS with principal component analysis, XPS, and NEXAFS spectroscopy. Analytical and Bioanalytical Chemistry, 403(2), 613-623.
    [Bibtex]
    @article{Min_2012_652,
    Abstract = {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 ToF-SIMS, 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 pi*(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.},
    Author = {Min, H. and Girard-Lauriault, P. L. and Gross, T. and Lippitz, A. and Dietrich, P. and Unger, W. E. S.},
    Doi = {doi:10.1007/s00216-012-5862-5},
    Id = {652},
    Journal = {Analytical and Bioanalytical Chemistry},
    Keywords = {amine-sam ageing process tof-sims nexafs xps ray photoelectron-spectroscopy chemical-analysis vapor-deposition surface-analysis polymer-films multilayers allylamine silicon silane layers},
    Number = {2},
    Pages = {613-623},
    Title = {Ambient-ageing processes in amine self-assembled monolayers on microarray slides as studied by ToF-SIMS with principal component analysis, XPS, and NEXAFS spectroscopy},
    Volume = {403},
    Year = {2012},
    Bdsk-Url-1 = {http://dx.doi.org/10.1007/s00216-012-5862-5}}

2011

  • [DOI] Dietrich, P. M., Horlacher, T., Girard-Lauriault, P. L., Gross, T., Lippitz, A., Min, H., Wirth, T., Castelli, R., Seeberger, P., & Unger, W. E. S.. (2011). Multimethod Chemical Characterization of Carbohydrate-Functionalized Surfaces. Journal of Carbohydrate Chemistry, 30(4-6), 361-372.
    [Bibtex]
    @article{Dietrich_2011_656,
    Abstract = {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.},
    Author = {Dietrich, P. M. and Horlacher, T. and Girard-Lauriault, P. L. and Gross, T. and Lippitz, A. and Min, H. and Wirth, T. and Castelli, R. and Seeberger, P. and Unger, W. E. S.},
    Doi = {doi:10.1080/07328303.2011.615181},
    Id = {656},
    Journal = {Journal of Carbohydrate Chemistry},
    Keywords = {carbohydrates microarrays self-assembled monolayers xps nexafs tof-sims ray photoelectron-spectroscopy self-assembled monolayers oligosaccharide synthesis gold},
    Number = {4-6},
    Pages = {361-372},
    Title = {Multimethod Chemical Characterization of Carbohydrate-Functionalized Surfaces},
    Volume = {30},
    Year = {2011},
    Bdsk-Url-1 = {http://dx.doi.org/10.1080/07328303.2011.615181}}
  • [DOI] Dietrich, P. M., Horlacher, T., Girard-Lauriault, P. L., Gross, T., Lippitz, A., Min, H., Wirth, T., Castelli, R., Seeberger, P. H., & Unger, W. E. S.. (2011). Adlayers of Dimannoside Thiols on Gold: Surface Chemical Analysis. Langmuir, 27(8), 4808-4815.
    [Bibtex]
    @article{Dietrich_2011_654,
    Abstract = {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 omega-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.},
    Author = {Dietrich, P. M. and Horlacher, T. and Girard-Lauriault, P. L. and Gross, T. and Lippitz, A. and Min, H. and Wirth, T. and Castelli, R. and Seeberger, P. H. and Unger, W. E. S.},
    Doi = {doi:10.1021/la104038q},
    Id = {654},
    Journal = {Langmuir},
    Keywords = {self-assembled monolayers ray photoelectron-spectroscopy carbohydrate-protein interactions microarrays spectra glycobiology absorption excitation binding oligosaccharides},
    Number = {8},
    Pages = {4808-4815},
    Title = {Adlayers of Dimannoside Thiols on Gold: Surface Chemical Analysis},
    Volume = {27},
    Year = {2011},
    Bdsk-Url-1 = {http://dx.doi.org/10.1021/la104038q}}
  • [DOI] Girard-Lauriault, P. L., Ruiz, J. C., Gross, T., Wertheimer, M. R., & Unger, W. E. S.. (2011). Ultra-Shallow Chemical Characterization of Organic Thin Films Deposited by Plasma and Vacuum-Ultraviolet, Using Angle- and Excitation Energy-Resolved XPS. Plasma Chemistry and Plasma Processing, 31(4), 535-550.
    [Bibtex]
    @article{Girard-Lauriault_2011_653,
    Abstract = {Nitrogen (N)-rich organic thin films were deposited using both low-pressure plasma- and vacuum-ultraviolet-based techniques, from mixtures of ammonia (NH(3)) and ethylene (C(2)H(4)). These films were investigated using angle-resolved and excitation energy resolved X-ray photoelectron spectroscopy (ARXPS and ERXPS, respectively) in order to determine their sub-surface chemical profiles. These two techniques enable one to tune the "XPS 95%" information depth, z (95%), by varying either the angle or the excitation energy. Using a combination of both techniques, z (95%) can be varied continuously from 0.7 to 11 nm. The surface-near chemistry is investigated using both high-resolution C 1s spectra and elemental concentrations derived from elemental peak intensities. Results show that while laboratory XPS, and even ARXPS, suggest homogenous surface chemistries, the novel combination of ARXPS and ERXPS points to the existence of a compositional profile in the extreme outer surface layer. Our conclusions are supported by simulations using SESSA software.},
    Author = {Girard-Lauriault, P. L. and Ruiz, J. C. and Gross, T. and Wertheimer, M. R. and Unger, W. E. S.},
    Doi = {doi:10.1007/s11090-011-9306-3},
    Id = {653},
    Journal = {Plasma Chemistry and Plasma Processing},
    Keywords = {plasma polymers vacuum ultraviolet photopolymers synchrotron xps depth profile ray photoelectron-spectroscopy mean free paths polymer-films atmospheric-pressure biomedical applications oxygen plasma surface polystyrene radiation profile},
    Number = {4},
    Pages = {535-550},
    Title = {Ultra-Shallow Chemical Characterization of Organic Thin Films Deposited by Plasma and Vacuum-Ultraviolet, Using Angle- and Excitation Energy-Resolved XPS},
    Volume = {31},
    Year = {2011},
    Bdsk-Url-1 = {http://dx.doi.org/10.1007/s11090-011-9306-3}}
  • [DOI] Petit, A., Demers, C. N., Girard-Lauriault, P. L., Stachura, D., Wertheimer, M. R., Antoniou, J., & Mwale, F.. (2011). Effect of nitrogen-rich cell culture surfaces on type X collagen expression by bovine growth plate chondrocytes. Biomedical Engineering Online, 10.
    [Bibtex]
    @article{Petit_2011_655,
    Abstract = {Background: Recent evidence indicates that osteoarthritis (OA) may be a systemic disease since mesenchymal stem cells (MSCs) from OA patients express type X collagen, a marker of late stage chondrocyte hypertrophy (associated with endochondral ossification). We recently showed that the expression of type X collagen was suppressed when MSCs from OA patients were cultured on nitrogen (N)-rich plasma polymer layers, which we call "PPE:N" (N-doped plasma-polymerized ethylene, containing up to 36 atomic percentage (at.%) of N.
    Methods: In the present study, we examined the expression of type X collagen in fetal bovine growth plate chondrocytes (containing hypertrophic chondrocytes) cultured on PPE:N. We also studied the effect of PPE: N on the expression of matrix molecules such as type II collagen and aggrecan, as well as on proteases (matrix metalloproteinase-13 (MMP-13) and molecules implicated in cell division (cyclin B2). Two other culture surfaces, "hydrophilic" polystyrene (PS, regular culture dishes) and nitrogen-containing cation polystyrene (Primaria (R)), were also investigated for comparison.
    Results: Results showed that type X collagen mRNA levels were suppressed when cultured for 4 days on PPE: N, suggesting that type X collagen is regulated similarly in hypertrophic chondrocytes and in human MSCs from OA patients. However, the levels of type X collagen mRNA almost returned to control value after 20 days in culture on these surfaces. Culture on the various surfaces had no significant effects on type II collagen, aggrecan, MMP-13, and cyclin B2 mRNA levels.
    Conclusion: Hypertrophy is diminished by culturing growth plate chondrocytes on nitrogen-rich surfaces, a mechanism that is beneficial for MSC chondrogenesis. Furthermore, one major advantage of such "intelligent surfaces" over recombinant growth factors for tissue engineering and cartilage repair is potentially large cost-saving.},
    Author = {Petit, A. and Demers, C. N. and Girard-Lauriault, P. L. and Stachura, D. and Wertheimer, M. R. and Antoniou, J. and Mwale, F.},
    Doi = {doi:10.1186/1475-925X-10-4},
    Id = {655},
    Journal = {Biomedical Engineering Online},
    Keywords = {mesenchymal stem-cells plasma-polymer films glow-discharge plasma atmospheric-pressure osteogenic differentiation endothelial-cells thin-films in-vitro proliferation attachment},
    Title = {Effect of nitrogen-rich cell culture surfaces on type X collagen expression by bovine growth plate chondrocytes},
    Volume = {10},
    Year = {2011},
    Bdsk-Url-1 = {http://dx.doi.org/10.1186/1475-925X-10-4}}

2010

  • [DOI] Girard-Lauriault, P. L., Retzko, I., Swaraj, S., Matsubayashi, N., Gross, T., Mix, R., & Unger, W. E. S.. (2010). Non-Destructive Sub-Surface Chemical Characterization of Air-Exposed Plasma Polymers by Energy-Resolved XPS. Plasma Process. Polym., 7(6), 474-481.
    [Bibtex]
    @article{Girard-Lauriault_2010_658,
    Abstract = {Plasma polymers containing oxygen- and nitrogen-based surface chemistries were prepared from allyl alcohol, allylamine and acrylic acid. Established selective chemical derivatisation procedures with trifluoroacetic anhydride (TFAA) and 4-trifluoromethyl benzaldehyde (TFBA) were used to determine alcohols and amines, respectively. Samples were analysed by energy-resolved XPS (ERXPS), enabling XPS depth resolution. We demonstrated that slightly aged plasma polymers prepared from allyl alcohol and allylamine present a homogeneous sub-surface chemistry within the range of the XPS information depth (approximate to 10 nm); this was clearly not the case for their acrylic acid counterparts. Furthermore, it is shown that standard derivatisation reactions result in homogeneous changes of the chemistry.},
    Author = {Girard-Lauriault, P. L. and Retzko, I. and Swaraj, S. and Matsubayashi, N. and Gross, T. and Mix, R. and Unger, W. E. S.},
    Date-Modified = {2014-07-03 20:23:03 +0000},
    Doi = {doi:10.1002/ppap.200900130},
    Id = {658},
    Journal = {Plasma Process. Polym.},
    Keywords = {depth profiling derivatisation plasma polymers synchrotron xps ray photoelectron-spectroscopy mean free paths atmospheric-pressure oxygen plasma films surface polystyrene radiation profile derivatization},
    Number = {6},
    Pages = {474-481},
    Title = {Non-Destructive Sub-Surface Chemical Characterization of Air-Exposed Plasma Polymers by Energy-Resolved XPS},
    Volume = {7},
    Year = {2010},
    Bdsk-Url-1 = {http://dx.doi.org/10.1002/ppap.200900130}}
  • [DOI] Petit, A., Wang, H. T., Girard-Lauriault, P. L., Wertheimer, M. R., Antoniou, J., & Mwale, F.. (2010). Novel insights into the mechanism of decreased expression of type X collagen in human mesenchymal stem cells from patients with osteoarthritis cultured on nitrogen-rich plasma polymers: Implication of cyclooxygenase-1. Journal of Biomedical Materials Research Part A, 94A(3), 744-750.
    [Bibtex]
    @article{Petit_2010_657,
    Abstract = {Recent evidence indicates that a major drawback of current cartilage- and intervertebral disc (IVD) tissue engineering is that human mesenchymal stem cells (MSCs) from patients with osteoarthritis rapidly express type X collagen (COL10A1), a marker of late stage chondrocyte hypertrophy associated with endochondral ossification. We recently demonstrated that COL10A1 expression was inhibited in MSCs from patients with osteoarthritis cultured on nitrogen-rich plasma polymerized (PPE:N) coatings. Here, we sought to understand the mechanisms of action of this effect by culturing MSCs on PPE:N surfaces in the presence of different inhibitors of kinases and cyclooxygenases. The effect of PPE:N surfaces on COL10A1 expression was found to be mimicked by the cyclooxygenase inhibitor NPPB, but not by daphnetin (an inhibitor of protein kinases) nor by genistein (an inhibitor of tyrosine kinases). COL10A1 expression was also suppressed by the specific cyclooxygenase-1 (COX-1: SC-560) and 5-lipoxygenase (5-LOX: MK-866) inhibitors, but not by COX-2 (COX-2 inhibitor 2) and 12-LOX (baicalein) inhibitors. Finally, the incubation of MSCs on PPE:N surfaces inhibited the expression of COX-1 while 5-LOX was not expressed in these cells. Taken together, these results indicate that PPE:N surfaces inhibit COL10A1 expression via the suppression of COX-1. (C) 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 94A: 744-750, 2010},
    Author = {Petit, A. and Wang, H. T. and Girard-Lauriault, P. L. and Wertheimer, M. R. and Antoniou, J. and Mwale, F.},
    Doi = {doi:10.1002/jbm.a.32739},
    Id = {657},
    Journal = {Journal of Biomedical Materials Research Part A},
    Keywords = {intervertebral disc tissue engineering collagen x gene expression mesenchymal stem cells plasma polymerization hypertrophic chondrocyte differentiation growth-plate chondrocytes activating transcription factor-2 glow-discharge plasma gene-expression parathyroid-hormone extracellular-matrix surface modification bone-marrow in-vivo},
    Number = {3},
    Pages = {744-750},
    Title = {Novel insights into the mechanism of decreased expression of type X collagen in human mesenchymal stem cells from patients with osteoarthritis cultured on nitrogen-rich plasma polymers: Implication of cyclooxygenase-1},
    Volume = {94A},
    Year = {2010},
    Bdsk-Url-1 = {http://dx.doi.org/10.1002/jbm.a.32739}}
  • [DOI] Ruiz, J. C., Girard-Lauriault, P. L., Truica-Marasescu, F., & Wertheimer, M. R.. (2010). Plasma- and vacuum-ultraviolet (VUV) photo-polymerisation of N- and O-rich thin films. Radiation Physics and Chemistry, 79(3), 310-314.
    [Bibtex]
    @article{Ruiz_2010_659,
    Abstract = {Nitrogen (N)- and oxygen (O)-rich organic thin films were deposited by vacuum-ultraviolet (VUV)-assisted photo-chemical polymerisation of flowing ethylene (C(2)H(4))-ammonia (NH(3)) and C(2)H(4)-nitrous oxide (N(2)O) mixtures of varying ratios, R, respectively. The reaction mechanism of these binary gas mixtures was investigated as a function of the wavelength, lambda, of two near-mono-chromatic VUV sources. Surface-near compositions of these "UV-PE:N" and "UV-PE:O" films were determined by X-ray photoelectron (XPS), and by Fourier transform (reflection-absorption) infrared (FTIR) spectroscopies. The two types of films were compared with plasma polymers deposited using low-pressure radiofrequency (r.f.) glow discharges in similar gas flow mixtures, "PPE:N" and 14 PPE:O". VUV-photochemistry appears to be superior to plasma-chemistry in its capability to produce nearly "mono-functional" organic thin films, ones that are rich in primary amines, -NH(2), and in carboxylic acid groups, -COOH, respectively. (C) 2009 Elsevier Ltd. All rights reserved.},
    Author = {Ruiz, J. C. and Girard-Lauriault, P. L. and Truica-Marasescu, F. and Wertheimer, M. R.},
    Doi = {doi:10.1016/j.radphyschem.2009.08.009},
    Id = {659},
    Journal = {Radiation Physics and Chemistry},
    Keywords = {ethylene n- and o-rich films photo-polymerisation vuv-photochemistry plasma polymerisation atmospheric-pressure polymer films biomedical applications deposition surfaces},
    Number = {3},
    Pages = {310-314},
    Title = {Plasma- and vacuum-ultraviolet (VUV) photo-polymerisation of N- and O-rich thin films},
    Volume = {79},
    Year = {2010},
    Bdsk-Url-1 = {http://dx.doi.org/10.1016/j.radphyschem.2009.08.009}}

2009

  • [DOI] Gigout, A., Levasseur, S., Girard-Lauriault, P. L., Buschmann, M. D., Wertheimer, M. R., & Jolicoeur, M.. (2009). CHO Cells Adhering to Nitrogen-Rich Plasma-Polymerised Ethylene Exhibit High Production of a Specific Recombinant Protein. Macromolecular Bioscience, 9(10), 979-988.
    [Bibtex]
    @article{Gigout_2009_660,
    Abstract = {In many industrial applications, inadequate cell attachment can be a limitation, especially when serum-free media are used. Nitrogen-rich plasma-polymerised ethylene (PPE:N) exhibits high concentrations of polar groups that can help to promote the attachment of weakly adherent cell types. Tissue plasminogen activatorproducing Chinese hamster ovary (CHO) cells adapted to suspension, were grown in the presence PPE:N flakes and were found to adhere to them. The growth rate was reduced, but cell viability was enhanced and their metabolism was more efficient, with generally higher recombinant protein productivity. Finally, cell adhesion on PPE:N surfaces was found to be independent of integrins, and was probably mediated by certain non-specific interactions with the PPE:N surface.},
    Author = {Gigout, A. and Levasseur, S. and Girard-Lauriault, P. L. and Buschmann, M. D. and Wertheimer, M. R. and Jolicoeur, M.},
    Doi = {doi:10.1002/mabi.200900079},
    Id = {660},
    Journal = {Macromolecular Bioscience},
    Keywords = {adhesion biomaterial biotechnology mammalian cells plasma polymerisation atmospheric-pressure microcarrier culture functional-groups integrin binding serum-proteins animal-cells adhesion surface growth attachment},
    Number = {10},
    Pages = {979-988},
    Title = {CHO Cells Adhering to Nitrogen-Rich Plasma-Polymerised Ethylene Exhibit High Production of a Specific Recombinant Protein},
    Volume = {9},
    Year = {2009},
    Bdsk-Url-1 = {http://dx.doi.org/10.1002/mabi.200900079}}
  • [DOI] Girard-Lauriault, P. L., Truica-Marasescu, F., Petit, A., Wang, H. T., Desjardins, P., Antoniou, J., Mwale, F., & Wertheimer, M. R.. (2009). Adhesion of Human U937 Monocytes to Nitrogen-Rich Organic Thin Films: Novel Insights into the Mechanism of Cellular Adhesion. Macromolecular Bioscience, 9(9), 911-921.
    [Bibtex]
    @article{Girard-Lauriault_2009_661,
    Abstract = {We present a two-fold study designed to elucidate the adhesion mechanism of human U937 monocytes on novel N-rich thin films deposited by plasma- and VUV photo-polymerisation, so-called "PVP:N" materials. It is shown that there exist sharply-defined ("critical") surface-chemical conditions that are necessary to induce cell adhesion. By comparing the film chemistries at the "critical" conditions, we demonstrate the dominant role of primary amines in the cell adhesion mechanism. Ouantitative real-time RT-PCR experiments using U937 cells that had adhered to PVP:N materials for up to 24h are presented, The adhesion induces a transient expression of cytokines, markers of macrophage activation, as well as a more sustained expression of PPAR gamma and ICAM-I.},
    Author = {Girard-Lauriault, P. L. and Truica-Marasescu, F. and Petit, A. and Wang, H. T. and Desjardins, P. and Antoniou, J. and Mwale, F. and Wertheimer, M. R.},
    Doi = {doi:10.1002/mabi.200800359},
    Id = {661},
    Journal = {Macromolecular Bioscience},
    Keywords = {biomaterials cell adhesion gene expression plasma polymerisation primary amines plasma-polymer films tumor-necrosis-factor endothelial-cells atmospheric-pressure in-vitro biomedical applications transcription factors molecule expression gene-expression ppar-gamma},
    Number = {9},
    Pages = {911-921},
    Title = {Adhesion of Human U937 Monocytes to Nitrogen-Rich Organic Thin Films: Novel Insights into the Mechanism of Cellular Adhesion},
    Volume = {9},
    Year = {2009},
    Bdsk-Url-1 = {http://dx.doi.org/10.1002/mabi.200800359}}

2008

  • [DOI] Girard-Lauriault, P. L., Desjardins, P., Unger, W. E. S., Lippitz, A., & Wertheimer, M. R.. (2008). Chemical characterisation of nitrogen-rich plasma-polymer films deposited in dielectric barrier discharges at atmospheric pressure. Plasma Process. Polym., 5(7), 631-644.
    [Bibtex]
    @article{Girard-Lauriault_2008_662,
    Abstract = {We have used an atmospheric pressure DBD apparatus to deposit novel families of N-rich plasma polymers (PP:N), using mixtures of three different hydrocarbon precursors in nitrogen at varying respective gas flow ratios. This research focuses on the overall chemical characterisation of those materials with specific attention to (semi)-quantitative analysis of functional groups. Well-established and some lesser-known analytical techniques have been combined to provide the best possible chemical and structural characterisations of these three families of PP:N thin films, namely XPS, NEXAFS and FT-IR spectroscopy.},
    Author = {Girard-Lauriault, P. L. and Desjardins, P. and Unger, W. E. S. and Lippitz, A. and Wertheimer, M. R.},
    Date-Modified = {2014-07-03 20:23:29 +0000},
    Doi = {doi:10.1002/ppap.200800054},
    Id = {662},
    Journal = {Plasma Process. Polym.},
    Keywords = {amines biomaterials deposition dielectric barrier discharges (dbd) esca/xps nexafs plasma polymerization in-situ characterization biomedical applications surface modification nexafs spectroscopy allylamine films acrylic-acid xps coatings adhesion functionalities},
    Number = {7},
    Pages = {631-644},
    Title = {Chemical characterisation of nitrogen-rich plasma-polymer films deposited in dielectric barrier discharges at atmospheric pressure},
    Volume = {5},
    Year = {2008},
    Bdsk-Url-1 = {http://dx.doi.org/10.1002/ppap.200800054}}
  • [DOI] Truica-Marasescu, F., Girard-Lauriault, P. L., Lippitz, A., Unger, W. E. S., & Wertheimer, M. R.. (2008). Nitrogen-rich plasma polymers: Comparison of films deposited in atmospheric- and low-pressure plasmas. Thin Solid Films, 516(21), 7406-7417.
    [Bibtex]
    @article{Truica-Marasescu_2008_663,
    Abstract = {Low- and atmospheric-pressure plasma co-polymerisations of binary gas mixtures of C(2)H(4) and NH(3) or N(2), respectively, were investigated for depositing N-rich plasma polymer coatings for biomedical applications. Deposition kinetics and relevant surface characteristics of resulting plasma polymerised ethylene enriched with nitrogen, "PPE:N", coatings were investigated as a function of the gas mixture ratio, X=NH(3)(N(2))/C(2)H(4). Physico-chemical properties of the coatings were determined using a combination of complementary surface-sensitive techniques: for example, total nitrogen concentrations, [N], up to 40 at.% were measured by X-ray Photoelectron Spectroscopy, XPS, while those of primary amines, [-NH(2)], were determined by performing chemical derivatisation followed by XPS analyses. PPE:N films were further characterised by UV-VIS Ellipsometry, Near Edge X-ray Absorption Fine Structure Spectroscopy, IR Spectroscopy and by Contact Angle Goniometry measurements. The stability of the coatings was tested, both in terms of water solubility and of "ageing" in ambient atmosphere. For the latter, selected samples were stored in the laboratory for different durations, in order to assess possible changes in their chemical structures. (c) 2008 Elsevier B.V. All rights reserved.},
    Author = {Truica-Marasescu, F. and Girard-Lauriault, P. L. and Lippitz, A. and Unger, W. E. S. and Wertheimer, M. R.},
    Doi = {doi:10.1016/j.tsf.2008.02.033},
    Id = {663},
    Journal = {Thin Solid Films},
    Keywords = {aging deposition process ethylene fourier transform infrared spectroscopy (ftir) glow discharge plasma polymers surface chemistry surface energy absorption spectroscopy nexafs in-situ characterization mesenchymal stem-cells glow-discharge plasma surface modification polyolefin surfaces chemical-analysis allylamine films acrylic-acid h films},
    Number = {21},
    Pages = {7406-7417},
    Title = {Nitrogen-rich plasma polymers: Comparison of films deposited in atmospheric- and low-pressure plasmas},
    Volume = {516},
    Year = {2008},
    Bdsk-Url-1 = {http://dx.doi.org/10.1016/j.tsf.2008.02.033}}

2007

  • [DOI] Lerouge, S., Major, A., Girard-Lauriault, P. L., Raymond, M. A., Laplante, P., Soulez, G., Mwale, F., Wertheimer, M. R., & Hebert, M. J.. (2007). Nitrogen-rich coatings for promoting healing around stent-grafts after endovascular aneurysm repair. Biomaterials, 28(6), 1209-1217.
    [Bibtex]
    @article{Lerouge_2007_665,
    Abstract = {Complications following endovascular aneurysm repair (EVAR) are related to deficient healing around the stent-graft (SG). New generations of SG with surface properties that foster vascular repair could overcome this limitation. Our goal was to evaluate the potential of a new nitrogen-rich plasma-polymerised biomaterial, designated PPE:N, as an external coating for polyethylene terephtalate (PET)- or polytetrafluoro-ethylene (PTFE)-based SGs, to promote healing around the implant. Thin PPE:N coatings were deposited on PET and PTFE films. Then, adhesion, growth, migration and resistance to apoptosis of vascular smooth muscle cells (VSMCs) and fibroblasts, as well as myofibroblast differentiation, were assessed in vitro. In another experimental group, chondroitin sulphate (CS), a newly described mediator of vascular repair, was added to normal culture medium, to search for possible additional benefit. PPE:N-coatings, especially on PET, increased and accelerated cell adhesion and growth, compared with control PET and with standard polystyrene culture plates (PCP). PPE:N was also found to increase the resistance to apoptosis in VSMC, an important finding as aneurysms are characterised by VMSC depletion caused by a pro-apoptotic phenotype. Addition of CS in solution further increased migration and resistance to apoptosis. In conclusion, PPE:N-coating and/or CS could promote vascular repair around SGs following EVAR. (c) 2006 Elsevier Ltd. All rights reserved.},
    Author = {Lerouge, S. and Major, A. and Girard-Lauriault, P. L. and Raymond, M. A. and Laplante, P. and Soulez, G. and Mwale, F. and Wertheimer, M. R. and Hebert, M. J.},
    Doi = {doi:10.1016/j.biomaterials.2006.10.033},
    Id = {665},
    Journal = {Biomaterials},
    Keywords = {aneurysm stent-graft plasma polymerisation chondroitin sulphate cell adhesion apoptosis abdominal aortic-aneurysms cells in-vitro growth-factor plasma apoptosis migration expression fixation anoikis binding},
    Number = {6},
    Pages = {1209-1217},
    Title = {Nitrogen-rich coatings for promoting healing around stent-grafts after endovascular aneurysm repair},
    Volume = {28},
    Year = {2007},
    Bdsk-Url-1 = {http://dx.doi.org/10.1016/j.biomaterials.2006.10.033}}
  • [DOI] Mwale, F., Wang, H. T., Petit, A., Girard-Lauriault, P. L., Hunter, C. J., Ouellet, J. A., Wertheimer, M. R., & Antoniou, J.. (2007). The effect of novel nitrogen-rich plasma polymer coatings on the phenotypic profile of notochordal cells. Biomedical Engineering Online, 6.
    [Bibtex]
    @article{Mwale_2007_664,
    Abstract = {Background: The loss of the notochordal cells from the nucleus pulposus is associated with ageing and disc degeneration. However, understanding the mechanisms responsible for the loss of these cells has been hampered in part due to the difficulty of culturing and maintaining their phenotype. Furthermore, little is known about the influence of the substratum on the molecular markers of notochordal cells. Methods: Notochordal cells were isolated from lumbar spine of non-chondrodystrophoid dogs and cultured on N-rich plasma polymer layers, so-called "PPE:N" ( N-doped plasma-polymerised ethylene, containing up to 36% [N]) surfaces, for 3, 7 or 14 days. Gene expression of vimentin ( VIM), pleiotrophin ( PTN), matrix Gla protein ( MGP), cartilage oligomeric matrix protein ( COMP), keratin 18 ( KRT 18), aggrecan ( AGG), collagen type 1 ( COL1A2), collagen type 2 ( COL2A1) was analyzed through semi-quantitative reverse transcription-polymerase chain reaction ( RT-PCR).
    Results: Notochordal cells were maintained in culture on PPE:N for up to 14 days with no loss in cell viability. Except for VIM, gene expression varied depending on the culture periods and [ N] concentration of the substratum. Generally, PPE: N surfaces altered gene expression significantly when cells were cultured for 3 or 7 days.
    Conclusion: The present study has shown that notochordal cells from dogs can attach to and grow on PPE: N surfaces. Analysis of the expression of different genes in these cells cultured on different N-functionalized surfaces indicates that cellular behaviour is gene-specific and time-dependent. Further studies are required to better understand the roles of specific surface functionalities on receptor sites, and their effects on cellular phenotypes.},
    Author = {Mwale, F. and Wang, H. T. and Petit, A. and Girard-Lauriault, P. L. and Hunter, C. J. and Ouellet, J. A. and Wertheimer, M. R. and Antoniou, J.},
    Doi = {doi:10.1186/1475-925X-6-33},
    Id = {664},
    Journal = {Biomedical Engineering Online},
    Keywords = {human intervertebral-disk glow-discharge plasma nucleus pulposus extracellular-matrix intermediate-filaments surface modification regional-variations drug-delivery biomaterials degeneration},
    Title = {The effect of novel nitrogen-rich plasma polymer coatings on the phenotypic profile of notochordal cells},
    Volume = {6},
    Year = {2007},
    Bdsk-Url-1 = {http://dx.doi.org/10.1186/1475-925X-6-33}}

2006

  • [DOI] Mwale, F., Girard-Lauriault, P. L., Wang, H. T., Lerouge, S., Antoniou, J., & Wertheimer, M. R.. (2006). Suppression of genes related to hypertrophy and osteogenesis in committed human mesenchymal stem cells cultured on novel nitrogen-rich plasma polymer coatings. Tissue Engineering, 12(9), 2639-2647.
    [Bibtex]
    @article{Mwale_2006_666,
    Abstract = {Mesenchymal stem cells (MSCs) are pluripotent progenitor cells with the ability to generate cartilage, bone, muscle, tendon, ligament, and fat. However, recent evidence indicates that a major drawback of current cartilage- and intervertebral disc-tissue engineering is that human MSCs isolated from some arthritic patients (a clinically relevant source of stem cells) express type X collagen (a marker of chondrocyte hypertrophy associated with endochondral ossification) and osteogenic markers. Some studies have attempted to use growth factors to inhibit type X collagen expression, but none has addressed the possible effect of the chemical composition of the substratum on chondrocyte hypertrophy and osteogenesis. Here, we examine the growth and differentiation potential of human MSCs cultured on nitrogen (N)-rich plasma polymer layers (N-doped plasma-polymerized ethylene, containing up to 36% nitrogen; PPE:N). We show that PPE:N almost completely suppresses the expression not only of type X collagen, but also of osteogenic marker genes such as alkaline phosphatase, bone sialoprotein, and osteocalcin. In contrast, neither aggrecan nor type I collagen expression were significantly affected. These results indicate that PPE: N coatings may be suitable surfaces for inducing MSCs to a chondrocyte or disc-like phenotype for tissue engineering of cartilage or intervertebral discs, in which hypertrophy and osteogenesis are suppressed.},
    Author = {Mwale, F. and Girard-Lauriault, P. L. and Wang, H. T. and Lerouge, S. and Antoniou, J. and Wertheimer, M. R.},
    Doi = {doi:10.1089/ten.2006.12.2639},
    Id = {666},
    Journal = {Tissue Engineering},
    Keywords = {human bone-marrow in-vitro chondrogenic differentiation extracellular-matrix growth-plate x collagen expression cartilage surfaces adhesion},
    Number = {9},
    Pages = {2639-2647},
    Title = {Suppression of genes related to hypertrophy and osteogenesis in committed human mesenchymal stem cells cultured on novel nitrogen-rich plasma polymer coatings},
    Volume = {12},
    Year = {2006},
    Bdsk-Url-1 = {http://dx.doi.org/10.1089/ten.2006.12.2639}}

2005

  • [DOI] Girard-Lauriault, P. L., Mwale, F., Iordanova, M., Demers, C., Desjardins, P., & Wertheimer, M. R.. (2005). Atmospheric pressure deposition of micropatterned nitrogen-rich plasma-polymer films for tissue engineering. Plasma Process. Polym., 2(3), 263-270.
    [Bibtex]
    @article{Girard-Lauriault_2005_667,
    Abstract = {A novel atmospheric-pressure plasma-polymerised thin film material has been deposited on various substrates using a pilot scale dielectric barrier discharge (DBD) reactor. Deposition kinetics and physico-chemical 1 characterisation data of nitrogen-rich plasma-polymerised ethylene (PPE:N) films, obtained using feed gas mixtures of N-2 (ca. 10 slm) and C2H4 (ca. 10 seem) are described. Nitrogen concentrations, [N], in the PPE:N films up to ca. 40% were determined by XPS; the concentrations of N-functionality of greatest interest, primary amines, were determined by chemical derivatisation with 4-trifluoromethyl-benzaldehyde. The PPE:N films were further characterised by attenuated total reflectance infra-red spectroscopy (ATR-FTIR), contact angle goniometry, and atomic force microscopy (AFM). Square arrays of PPE:N "islands", for example 30 mu m in diameter repeated every 200 gm, were deposited on polymers, for example biaxially oriented poly(propylene) (BOPP), through specially-prepared Kapton (R) polyimide masks. Cell culture experiments were then conducted on these micro-patterned surfaces, using various cell types of interest in orthopaedics, for example growth plate and articular chondrocytes, or human U937 macrophages, the latter of which do not adhere to existing cell culture dishes. In all these cases the cells rapidly adhered and proliferated on the PPE:N islands, but not elsewhere on the polymer surfaces. In an effort to gain insight into cell adhesion mechanisms, adhesion of both macrophages and chondrocytes was tested against films with different [N] values. U-937 macrophages adhered to films containing 25% or more [N], but not at all to films with lower values of [N], suggesting the existence of a "critical" value, [N](crit), necessary to induce cell adhesion.},
    Author = {Girard-Lauriault, P. L. and Mwale, F. and Iordanova, M. and Demers, C. and Desjardins, P. and Wertheimer, M. R.},
    Date-Modified = {2014-07-03 20:23:59 +0000},
    Doi = {doi:10.1002/ppap.200400092},
    Id = {667},
    Journal = {Plasma Process. Polym.},
    Keywords = {biomaterials cell adhesion cell patterning deposition dielectric barrier discharges (dbd) human u937 macrophages expression surfaces},
    Number = {3},
    Pages = {263-270},
    Title = {Atmospheric pressure deposition of micropatterned nitrogen-rich plasma-polymer films for tissue engineering},
    Volume = {2},
    Year = {2005},
    Bdsk-Url-1 = {http://dx.doi.org/10.1002/ppap.200400092}}