Article
Chemistry, Physical
Paolo Branchini, Valentina Spampinato, Alexis Franquet, Gianlorenzo Bussetti, Luca Tortora, Stefania De Rosa
Summary: Intercalation mechanisms, diffusion, and segregation phenomena have significant implications in various fields of applied science involving graphitic materials. This study investigates the effects of different ion sources and energy conditions on the structure and chemistry of graphite through depth profiling experiments, aiming to determine the optimal conditions for preserving the crystal features.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Sarah E. Bamford, Robert T. Jones, Wil Gardner, Benjamin W. Muir, David A. Winkler, Paul J. Pigram
Summary: This work presents a 3D chemical characterization of a low emissivity double silver coating on glass using time-of-flight secondary ion mass spectrometry (ToF-SIMS) and machine learning. The composition of different layers is visualized using an unsupervised machine learning technique. Repeating layers are identified based on their mass spectra and classified as chemically indistinguishable. This technique provides valuable insight into manufacturing processes and production challenges, and has strong potential in forensic applications.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Multidisciplinary Sciences
Marko Barac, Marko Brajkovic, Zdravko Siketic, Jernej Ekar, Iva Bogdanovic Radovic, Iva Srut Rakic, Janez Kovac
Summary: This study explores the possibility of depth profiling of inorganic materials using low energy primary ions. The results demonstrate the potential application of low energy primary ions in depth profiling compared to other analysis methods.
SCIENTIFIC REPORTS
(2022)
Article
Engineering, Mechanical
Nasrya F. Kossoko, Frederic Dubreuil, Benoit Thiebaut, Michel Belin, Clotilde Minfray
Summary: This paper investigates the tribological conditions required to achieve low friction with a diblock PIB-PEG polymer friction modifier in base oil under severe lubrication regimes. The study found a very low friction coefficient at high temperatures, and characterized the formation of a polymer film on rubbing surfaces and its bonding to the steel substrate through polar functions.
TRIBOLOGY INTERNATIONAL
(2021)
Article
Chemistry, Physical
Junichiro Sameshima, Shigenori Numao
Summary: This study experimentally investigated the behavior and mechanism of background signals during depth profiling of atmospheric elements using dual-beam TOF-SIMS on silicon wafers. It was found that the background signals of atmospheric elements are inversely proportional to the sputtering rate, mainly attributed to the accumulation of components through adsorption and ion bombardment in the pre-equilibrium state. Additionally, H2O dominates the background formation process of hydrogen and oxygen, while the background signal levels of carbon with respect to the sputtering rate show a different trend than other elements.
SURFACE AND INTERFACE ANALYSIS
(2022)
Article
Chemistry, Physical
Amal Ben Hadj Mabrouk, Christophe Licitra, Antoine Chateauminois, Marc Veillerot
Summary: This study investigated the impact of PMMA thin film molecular weight on ToF-SIMS sputtering mechanisms and kinetics, revealing a decrease in sputtering yield volume with increasing molecular weight. Physical parameters such as glass transition temperature and polymer chain entanglement were discussed in relation to this behavior, with sputtering yield variation found to logarithmically correlate with primary beam energy. Preliminary experiments with low molecular weight PMMA also showed a nanoconfinement effect similar to argon cluster sputtering but of lesser magnitude.
SURFACE AND INTERFACE ANALYSIS
(2021)
Article
Chemistry, Physical
Michael Leitzenberger, Peter Kuegler, Stefan Krivec, Herbert Hutter
Summary: Artifact-free depth profiles of alkali ions in SiO2 were obtained using ToF-SIMS with Cs+ beam as sputter gun, demonstrating the effectiveness of the method. The approach allows for accurate depth profiling without the need for advanced equipment, making it more accessible to laboratories.
SURFACE AND INTERFACE ANALYSIS
(2021)
Article
Chemistry, Analytical
Wil Gardner, David A. Winkler, Suzanne M. Cutts, Steven A. Torney, Geoffrey A. Pietersz, Benjamin W. Muir, Paul J. Pigram
Summary: Feature extraction algorithms are important for reducing data dimensionality, but most methods do not consider spatial information. This study introduces a convolutional autoencoder algorithm that can be applied to hyperspectral ToF-SIMS imaging and achieves better results.
ANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Analytical
Benjamin Tomasetti, Cleiment Lauzin, Arnaud Delcorte
Summary: A method called microvolume expansion is developed to overcome the negative effects of molecular entanglement, ionization-suppressive neighbors, and unfavorable sample substrate in time-of-flight secondary ion mass spectrometry (ToF-SIMS). The method utilizes large argon clusters to transfer biomolecules from a target to a collector in vacuum. It has been successfully applied to expand phosphatidylcholine (PC) lipid and analyze complex biological assemblies.
ANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Analytical
Wil Gardner, David A. Winkler, Suzanne M. Cutts, Steven A. Torney, Geoffrey A. Pietersz, Benjamin W. Muir, Paul J. Pigram
Summary: Feature extraction algorithms are important for reducing data dimensionality, but most methods do not consider spatial information. This study introduces a convolutional autoencoder (CNNAE) specifically designed for hyperspectral ToF-SIMS imaging data, which incorporates pixel neighborhood information through convolutional layers. Compared to other methods, the CNNAE produces features with higher contrast and autocorrelation, accurately representing histologically recognizable features in the data. Additionally, the extension of CNNAE to 3D ToF-SIMS images provides a proof of principle for analyzing more complex 3D datasets.
ANALYTICAL CHEMISTRY
(2022)
Article
Materials Science, Multidisciplinary
Olga S. Ovchinnikova, Nikolay Borodinov, Artem A. Trofimov, Steven T. King, Matthias Lorenz, William Lamberti, David Abmayr, Anton Ievlev
Summary: Chemical imaging of polymers and polymer blends has traditionally been done using ToF-SIMS with limited spatial resolution, but recent work has focused on using HIM-SIMS for higher resolution. By utilizing HIM-SIMS, differentiation between PE and PP as well as imaging of phase-separated domains within PE has been achieved, demonstrating its potential for analyzing complex polymeric systems.
ACS APPLIED POLYMER MATERIALS
(2021)
Article
Chemistry, Physical
Shin Muramoto, Daniel J. Graham
Summary: Secondary ion mass spectrometry using argon cluster primary ion beam allows molecular compositional depth profiling in organic thin films with minimal loss of chemical information. However, thicker organic films can lead to the rapid formation of micron-scale topography, affecting sputter yield linearity and depth resolution. To minimize 3D reconstruction distortions, a staggered sample rotation method was employed. By measuring depth resolution at the film-sphere interface, the effect of micron-scale topography and sample rotation on depth profile quality could be quantitatively assessed.
SURFACE AND INTERFACE ANALYSIS
(2021)
Article
Nanoscience & Nanotechnology
Yue Feng, Bon Min Koo, Antoine Seyeux, Jolanta Swiatowska, Catherine Henry de Villeneuve, Michel Rosso, Francois Ozanam
Summary: Pure and methylated amorphous silicon thin films were analyzed using time-of-flight secondary ion mass spectrometry to study the lithiation mechanism and biphasic process. Lithiation induced swelling and roughening of the active layer. No measurable Li diffusion was observed after lithiation. Distinct Li profiles were observed for the two materials, with the methylated film showing a slower Li concentration decrease attributed to the presence of nanovoids.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Biochemistry & Molecular Biology
Agnieszka Kaminska, Magdalena E. Marzec, Ewa L. Stepien
Summary: This study tested and optimized silicon surface functionalization procedures for capturing urinary extracellular vesicles (uEVs), investigating the influence of silane type and protein concentration on binding efficiency, observing changes in the biosensor surface using surface characterization techniques, purifying uEVs by a low-vacuum filtration method and concentrating them by ultracentrifugation, and determining physical parameters of uEVs post-isolation. Results showed gradual growth of the molecular layer after modification stages, with no significant changes in characteristic peaks of amino acids and lipids in positive and negative polarization. The optimal concentration of lactadherin protein for the tested system was found to be 25 μg/mL.
Article
Materials Science, Multidisciplinary
A. Franquet, V. Spampinato, S. Kayser, W. Vandervorst, P. van der Heide
Summary: Shrinking semiconductor device dimensions require new methods and technologies for materials characterization. SF-SIMS and OrbitrapTM-SIMS methods have been demonstrated to accurately quantify impurities in small structures.
Article
Chemistry, Physical
Thomas Webb, Xueping Liu, Robert J. E. Westbrook, Stefanie Kern, Muhammad T. Sajjad, Sandra Jenatsch, K. D. G. Imalka Jayawardena, W. Hashini K. Perera, Igor P. Marko, Sanjayan Sathasivam, Bowei Li, Mozhgan Yavari, David J. Scurr, Morgan R. Alexander, Thomas J. Macdonald, Saif A. Haque, Stephen J. Sweeney, Wei Zhang
Summary: A new approach is presented in this paper to address the issue of dopant induced instability in high efficiency perovskite solar cells (PSCs). By utilizing organometallocenes, significant improvements are observed in device stability and hole extraction efficiency at the hole transporting layer (HTL) interface.
ADVANCED ENERGY MATERIALS
(2022)
Article
Pharmacology & Pharmacy
Phoebe McCrorie, Jonathan Rowlinson, David J. Scurr, Maria Marlow, Ruman Rahman
Summary: Historically, pre-clinical neuro-oncological drug delivery studies have primarily relied on overall animal survival as a measure of efficacy. However, this study demonstrates the potential of OrbiSIMS, a next-generation analytical instrument, to accurately detect brain penetration of drug compounds and provide imaging capabilities. This method could complement in vivo efficacy studies and assess the distribution and penetration of drugs in the brain.
Article
Biochemistry & Molecular Biology
Valentina Cuzzucoli Crucitti, Aleksandar Ilchev, Jonathan C. Moore, Harriet R. Fowler, Jean-Frederic Dubern, Olutoba Sanni, Xuan Xue, Bethany K. Husband, Adam A. Dundas, Sean Smith, Joni L. Wildman, Vincenzo Taresco, Paul Williams, Morgan R. Alexander, Steven M. Howdle, Ricky D. Wildman, Robert A. Stockman, Derek J. Irvine
Summary: This study utilized the alpha parameter, a molecular descriptor, to design terpene-based polymers resistant to biofilm formation by Pseudomonas aeruginosa. The potential biofilm resistance of terpene-derived monomers was predicted and ranked using the alpha parameter. The monomers from commercially available terpenes were polymerized and confirmed to have biofilm resistance properties. The scaled-up monomers were successfully printed and used to create bio-instructive microparticles. The observations in this study have significant potential to produce bio-resistant coatings, packaging materials, fibers, and medical devices.
Article
Pharmacology & Pharmacy
Paula Muresan, Phoebe McCrorie, Fiona Smith, Catherine Vasey, Vincenzo Taresco, David J. Scurr, Stefanie Kern, Stuart Smith, Pavel Gershkovich, Ruman Rahman, Maria Marlow
Summary: This study developed polymeric microneedle (MN) patches for the treatment of CNS tumors. The results demonstrated successful drug release and penetration, providing a potential solution for local brain drug delivery.
EUROPEAN JOURNAL OF PHARMACEUTICS AND BIOPHARMACEUTICS
(2023)
Article
Chemistry, Medicinal
Albatool Sabeeh Al-Badry, Mohammed Hussain Al-Mayahy, David J. Scurr
Summary: Hydrogel microneedles offer a promising approach for delivering drug molecules across the skin in a sustained release manner. The use of hydrogel microneedles containing acyclovir could improve bioavailability and patient compliance while reducing gastrointestinal side effects. The optimal formulation of the hydrogel microneedle array was found to have suitable needle formation, mechanical strength, and drug release over a 24-hour period. The permeation of acyclovir from the hydrogel microneedle array was significantly increased compared to the control, and the array was able to deliver a high percentage of the loading dose over 24 hours.
JOURNAL OF PHARMACEUTICAL SCIENCES
(2023)
Article
Multidisciplinary Sciences
Jean-Frederic Dubern, Andrew L. Hook, Alessandro M. Carabelli, Chien-Yi Chang, Christopher A. Lewis-Lloyd, Jeni C. Luckett, Laurence Burroughs, Adam A. Dundas, David J. Humes, Derek J. Irvine, Morgan R. Alexander, Paul Williams
Summary: Innovative approaches are urgently needed to prevent catheter-associated urinary tract infections (CAUTIs). A newly discovered acrylate copolymer has shown promising resistance against bacterial biofilm formation, swarming, encrustation, and host protein deposition, all of which are major challenges in preventing CAUTIs. The copolymer, poly(tert-butyl cyclohexyl acrylate), combined with poly(2-hydroxy-3-phenoxypropyl acrylate) has demonstrated its potential as a urinary catheter coating by retaining its bioinstructive properties and maintaining resistance against various uropathogens.
Article
Neurosciences
Franziska Linke, James E. C. Johnson, Stefanie Kern, Christopher D. Bennett, Anbarasu Lourdusamy, Daniel Lea, Steven C. Clifford, Catherine L. R. Merry, Snow Stolnik, Morgan R. Alexander, Andrew C. Peet, David J. Scurr, Rian L. Griffiths, Anna M. Grabowska, Ian D. Kerr, Beth Coyle
Summary: By comparing the most aggressive subgroup (Group 3) with the intermediate (SHH) subgroup, crucial differences in tumour heterogeneity were identified in medulloblastoma (MB) in children. Group 3 exhibited multiple subpopulations with enhanced oxidative phosphorylation and tricarboxylic acid (TCA) cycle activity, while SHH had unique matrix-producing subpopulations containing sulfur-containing species such as collagen organizer lumican. Patients with high fumarate levels and activated stress response pathways showed poorer survival. Inhibition of NRF2 increased sensitivity to vincristine in Group 3 MB.
ACTA NEUROPATHOLOGICA COMMUNICATIONS
(2023)
Article
Nanoscience & Nanotechnology
Leonardo Contreas, Andrew L. Hook, David A. Winkler, Grazziela Figueredo, Paul Williams, Charles A. Laughton, Morgan R. Alexander, Philip M. Williams
Summary: Bacterial infections are becoming a greater concern due to antimicrobial resistance. The rational design of materials resistant to biofilm formation is a crucial strategy to prevent infections related to medical devices. Machine learning has been used to identify strong associations between bacterial adhesion and the physicochemical properties of polyacrylate libraries. However, the interpretability of nonlinear models is limited, making it challenging to understand the molecular interactions between materials and bacteria.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Biophysics
Heba Khateb, Andrew L. Hook, Stefanie Kern, Julie A. Watts, Sonali Singh, Darryl Jackson, Luisa Marinez-Pomares, Paul Williams, Morgan R. Alexander
Summary: The use of OrbiTrap analyzer with SIMS (3D OrbiSIMS) enables label-free mass spectrometry of Psl, accurately identifying secondary ion peaks specific to the Psl structure. By studying P. aeruginosa biofilm and purified Psl, 17 peaks associated with Psl fragments within the biofilm matrix were confidently identified. Additionally, the neutral loss sequences approach can also identify multiple oligosaccharide fragments without a biological reference sample.
Article
Chemistry, Medicinal
Songtao Xue, Zhiwei Li, Xiaotong Ze, Xiuyuan Wu, Chen He, Wen Shuai, Maria Marlow, Jian Chen, David Scurr, Zheying Zhu, Jinyi Xu, Shengtao Xu
Summary: Excessive melanin deposition can cause various skin disorders. We discovered a series of novel tyrosinase inhibitor hybrids that can inhibit tyrosinase activity and reduce melanin content in the skin. Compound 11c showed the most potent activity against tyrosinase, with nanomolar IC50 values, significant antioxidant activity, and low cytotoxicity. It also exhibited excellent permeability in vitro and reduced melanin content in a guinea pig model of UV-induced skin pigmentation. Compound 11c holds promise as a potential therapy for treating skin hyperpigmentation.
JOURNAL OF MEDICINAL CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
See Yoong Wong, Andrew L. Hook, Wil Gardner, Chien-Yi Chang, Ying Mei, Martyn C. Davies, Paul Williams, Morgan R. Alexander, Davide Ballabio, Benjamin W. Muir, David A. Winkler, Paul J. Pigram
Summary: Biofilm formation is a major problem in hospitals, and researching biofilm-resistant materials is critical. Polymer microarrays can efficiently discover new biofilm-resistant polymers. This study investigates bacterial attachment and surface chemistry on a polymer microarray to better understand Pseudomonas aeruginosa biofilm formation. Analyzing the data using linear multivariate analysis and a nonlinear self-organizing map reveals fragment ions associated with bacterial biofilm formation. Considering these insights, a second analysis is conducted that explicitly considers interactions between key fragments. This improved model provides chemical insights for designing materials that prevent pathogen attachment.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Nanoscience & Nanotechnology
Kavya Ganabady, Nicola Contessi Negrini, Jacob C. Scherba, Brandon M. Nitschke, Morgan R. Alexander, Kyle H. Vining, Melissa A. Grunlan, David J. Mooney, Adam D. Celiz
Summary: In this study, we employed a high-throughput screening strategy to rapidly identify a biocompatible bone adhesive with high bond strength. Through thiol-ene click chemistry, a library of polymers was synthesized and a copolymer (1-S2-FT01) composed of TATATO and PETMP was identified as the most suitable candidate. This copolymer exhibited favorable mechanical properties, supported hMSC adhesion, adhered to bone tissue with similar strength to commercially available bone glues, and facilitated osteogenic differentiation of hMSCs and attachment of polymer scaffolds to bone tissue, making it an ideal alternative bone adhesive for orthopedic surgery.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Liam A. Crawford, Valentina Cuzzucoli Crucitti, Amy Stimpson, Chloe Morgan, Jonathan Blake, Ricky D. Wildman, Andrew L. Hook, Morgan R. Alexander, Derek J. Irvine, Simon V. Avery
Summary: This study demonstrates a novel approach to crop protection using polymer materials, which resulted in a significant reduction in infection rate and had no negative impact on wheat growth. These findings validate the potential of using non-eluting polymers for fungal control.
Article
Chemistry, Physical
James S. Sharp, Nathaniel M. Roberts
Summary: This study investigates the thickness dependence of telephone cord blister formation in solvent swollen PDMS thin films. By recording videos and using Python for analysis, the correlation between the width of telephone cord blisters, the wavelength of sinusoidal corrugations, blister growth rate, and film thickness is determined.
