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Wen K, Gorbushina AA, Schwibbert K, Bell J. Microfluidic Platform with Precisely Controlled Hydrodynamic Parameters and Integrated Features for Generation of Microvortices to Accurately Form and Monitor Biofilms in Flow. ACS Biomater Sci Eng 2024; 10:4626-4634. [PMID: 38904279 PMCID: PMC11234330 DOI: 10.1021/acsbiomaterials.4c00101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
Microorganisms often live in habitats characterized by fluid flow, and their adhesion to surfaces in industrial systems or clinical settings may lead to pipe clogging, microbially influenced corrosion, material deterioration, food spoilage, infections, and human illness. Here, a novel microfluidic platform was developed to investigate biofilm formation under precisely controlled (i) cell concentration, (ii) temperature, and (iii) flow conditions. The developed platform central unit is a single-channel microfluidic flow cell designed to ensure ultrahomogeneous flow and condition in its central area, where features, e.g., with trapping properties, can be incorporated. In comparison to static and macroflow chamber assays for biofilm studies, microfluidic chips allow in situ monitoring of biofilm formation under various flow regimes and have better environment control and smaller sample requirements. Flow simulations and experiments with fluorescent particles were used to simulate bacteria flow in the platform cell for calculating flow velocity and direction at the microscale level. The combination of flow analysis and fluorescent strain injection in the cell showed that microtraps placed at the center of the channel were efficient in capturing bacteria at determined positions and to study how flow conditions, especially microvortices, can affect biofilm formation. The microfluidic platform exhibited improved performances in terms of homogeneity and robustness for in vitro biofilm formation. We anticipate the presented platform to be suitable for broad, versatile, and high-throughput biofilm studies at the microscale level.
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Affiliation(s)
- Keqing Wen
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, Berlin 12205, Germany
- Freie Universität Berlin, Kaiserswerther Str. 16-18, Berlin 14195, Germany
| | - Anna A Gorbushina
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, Berlin 12205, Germany
- Freie Universität Berlin, Kaiserswerther Str. 16-18, Berlin 14195, Germany
| | - Karin Schwibbert
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, Berlin 12205, Germany
| | - Jérémy Bell
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, Berlin 12205, Germany
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Schell F, Zwahr C, Lasagni AF. Surfalize: A Python Library for Surface Topography and Roughness Analysis Designed for Periodic Surface Structures. NANOMATERIALS (BASEL, SWITZERLAND) 2024; 14:1076. [PMID: 38998681 PMCID: PMC11243480 DOI: 10.3390/nano14131076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2024] [Revised: 06/19/2024] [Accepted: 06/21/2024] [Indexed: 07/14/2024]
Abstract
Surface roughness measurement is an integral part of the characterization of microtextured surfaces. Multiple established software packages offer the calculation of roughness parameters according to ISO 25178. However, these packages lack a specific set of features, which we hope to address in this work. Firstly, they often lack or have limited capabilities for automated and batch analysis, making it hard to integrate into other applications. Secondly, they are often proprietary and therefore restrict access to some potential users. Lastly, they lack some capabilities when it comes to the analysis of periodic microtextured surfaces. Namely, common parameters such as the peak-to-valley depth, spatial period and homogeneity cannot be calculated automatically. This work aims to address these challenges by introducing a novel Python library, Surfalize, which intends to fill in the gaps regarding this functionality. The functionality is described and the algorithms are validated against established software packages or manual measurements.
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Affiliation(s)
- Frederic Schell
- Fraunhofer Institute for Material and Beam Technology IWS, Winterbergstraße 28, 01277 Dresden, Germany
| | - Christoph Zwahr
- Fraunhofer Institute for Material and Beam Technology IWS, Winterbergstraße 28, 01277 Dresden, Germany
| | - Andrés F. Lasagni
- Fraunhofer Institute for Material and Beam Technology IWS, Winterbergstraße 28, 01277 Dresden, Germany
- Institut für Fertigungstechnik, Technische Universität Dresden, George-Bähr-Str. 3c, 01069 Dresden, Germany
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3
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Tavangar A, Premnath P, Tan B, Venkatakrishnan K. Antifouling nanoplatform for controlled attachment of E. coli. Biomed Mater 2024; 19:045019. [PMID: 38772388 DOI: 10.1088/1748-605x/ad4e87] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Accepted: 05/21/2024] [Indexed: 05/23/2024]
Abstract
Biofouling is the most common cause of bacterial contamination in implanted materials/devices resulting in severe inflammation, implant mobilization, and eventual failure. Since bacterial attachment represents the initial step toward biofouling, developing synthetic surfaces that prevent bacterial adhesion is of keen interest in biomaterials research. In this study, we develop antifouling nanoplatforms that effectively impede bacterial adhesion and the consequent biofilm formation. We synthesize the antifouling nanoplatform by introducing silicon (Si)/silica nanoassemblies to the surface through ultrafast ionization of Si substrates. We assess the effectiveness of these nanoplatforms in inhibitingEscherichia coli(E. coli) adhesion. The findings reveal a significant reduction in bacterial attachment on the nanoplatform compared to untreated silicon, with bacteria forming smaller colonies. By manipulating physicochemical characteristics such as nanoassembly size/concentration and nanovoid size, we further control bacterial attachment. These findings suggest the potential of our synthesized nanoplatform in developing biomedical implants/devices with improved antifouling properties.
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Affiliation(s)
- Amirhossein Tavangar
- Department of Mathematics, Research Skills and Analysis, Humber College Institute of Technology, 205 Humber College Boulevard, Toronto, ON M9W 5L7, Canada
| | - Priyatha Premnath
- Department of Biomedical Engineering, College of Engineering and Applied Science, University of Wisconsin, 3200 North Cramer Street, Milwaukee, WI 53211, United States of America
| | - Bo Tan
- Nanocharacterization Laboratory, Department of Aerospace Engineering, Toronto Metropolitan University, 350 Victoria Street, Toronto, ON M5B 2K3, Canada
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, 36 Queen Street East, Toronto, ON M5B 1W8, Canada
| | - Krishnan Venkatakrishnan
- Ultrashort Laser Nanomanufacturing Research Facility, Department of Mechanical and Industrial Engineering, Toronto Metropolitan University, 350 Victoria Street, Toronto, ON M5B 2K3, Canada
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, 36 Queen Street East, Toronto, ON M5B 1W8, Canada
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4
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Simpson NG, Broadhead EJ, Casto AM, Tibbetts KM. Enhancement of Metal Nanostructure Deposition on Silicon Laser-Induced Periodic Surface Structures by Galvanic Replacement. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:241-250. [PMID: 38113511 DOI: 10.1021/acs.langmuir.3c02435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
We report a chemically motivated, single-step method to enhance metal deposition onto silicon laser-induced periodic surface structures (LIPSSs) using reactive laser ablation in liquid (RLAL). Galvanic replacement (GR) reactions were used in conjunction with RLAL (GR-RLAL) to promote the deposition of Au and Cu nanostructures onto a Si LIPSS. To increase the deposition of Au, sacrificial metals Cu, Fe, and Zn were used; Fe and Zn also enhanced the deposition of Cu. We show that the deposited metal content, surface morphology, and metal crystallite size can be tuned based on the difference in electrochemical potentials of the deposited and sacrificial metal. Compared to the Au and Cu reference samples, GR more than doubled the metal content on the LIPSS and reduced metal crystallite sizes by up to 20%. The ability to tune the metal content and crystalline domain size simultaneously makes GR-RLAL a potentially useful approach in the manufacturing of functional metal-LIPSS materials such as surface-enhanced Raman spectroscopy substrates.
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Affiliation(s)
- Nicholas G Simpson
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
| | - Eric J Broadhead
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
| | - Addison M Casto
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
| | - Katharine Moore Tibbetts
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284, United States
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5
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Daskalova A, Angelova L. Design of Surfaces with Persistent Antimicrobial Properties on Stainless Steel Developed Using Femtosecond Laser Texturing for Application in "High Traffic" Objects. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2396. [PMID: 37686904 PMCID: PMC10489816 DOI: 10.3390/nano13172396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/17/2023] [Accepted: 08/18/2023] [Indexed: 09/10/2023]
Abstract
Metal-based high-touch surfaces used for diverse applications in everyday use, like handrails, playground grab handles, doorknobs, ATM touch pads, and desks, are the most common targets for pollution with a variety of microbes; there is thus a need to improve their antimicrobial properties, an issue which has become a challenge in recent years, particularly after the COVID-19 pandemic. According to the World Health Organization (WHO), drug-resistant pathogens are one of the main concerns to global health today, as they lead to longer hospital stays and increased medical costs. Generally, the development of antimicrobial surfaces is related to the utilization of chemical methods via deposition on surfaces in the forms of various types of coatings. However, the addition of chemical substances onto a surface can induce unwanted effects, since it causes surface chemistry changes and, in some cases, cannot provide long-lasting results. A novel approach of utilising ultra-short laser radiation for the treatment of metallic surfaces by inducing a variety of micro- and nanostructuration is elaborated upon in the current research, estimating the optimum relation between the wettability and roughness characteristics for the creation of antimicrobial properties for such high-touch surfaces. In the current study, AISI 304-304L stainless steel metal was used as a benchmark material. Surface texturing via laser ablation with femtosecond laser pulses is an effective method, since it enables the formation of a variety of surface patterns, along with the creation of bimodal roughness, in one-step processing. In this investigation, a precise approach toward developing hydrophobic stainless steel surfaces with tunable adherence using femtosecond laser-induced modification is described. The impact of basic femtosecond laser processing parameters, like the scanning velocity, laser energy, and wettability properties of the laser-processed stainless steel samples, are examined. It is identified that the topography and morphology of laser-induced surface structures can be efficiently changed by adapting the laser processing parameters to create structures, which facilitate the transfer of surface properties from extremely low to high surface wettability.
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Affiliation(s)
- Albena Daskalova
- Institute of Electronics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., 1784 Sofia, Bulgaria;
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Evangelista I, Wencel D, Beguin S, Zhang N, Gilchrist MD. Influence of Surface Texturing on the Dry Tribological Properties of Polymers in Medical Devices. Polymers (Basel) 2023; 15:2858. [PMID: 37447503 DOI: 10.3390/polym15132858] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 06/25/2023] [Accepted: 06/25/2023] [Indexed: 07/15/2023] Open
Abstract
There is a constant need to improve patient comfort and product performance associated with the use of medical devices. Efforts to optimise the tribological characteristics of medical devices usually involve modifying existing devices without compromising their main design features and functionality. This article constitutes a state-of-the-art review of the influence of dry friction on polymeric components used in medical devices, including those having microscale surface features. Surface tribology and contact interactions are discussed, along with alternative forms of surface texturing. Evident gaps in the literature, and areas warranting future research are highlighted; these include friction involving polymer Vs polymer surfaces, information regarding which topologies and feature spacings provide the best performing textured surfaces, and design guidelines that would assist manufacturers to minimise or maximise friction under non-lubricated conditions.
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Affiliation(s)
- Isabela Evangelista
- School of Mechanical & Materials Engineering, University College Dublin, Belfield, D04 V1W8 Dublin, Ireland
- BD (Becton, Dickinson & Company), Blackrock Business Park, Carysfort Avenue, Blackrock, A94 H2X4 Dublin, Ireland
| | - Dorota Wencel
- BD (Becton, Dickinson & Company), Blackrock Business Park, Carysfort Avenue, Blackrock, A94 H2X4 Dublin, Ireland
| | - Steve Beguin
- BD (Becton, Dickinson & Company), Blackrock Business Park, Carysfort Avenue, Blackrock, A94 H2X4 Dublin, Ireland
| | - Nan Zhang
- School of Mechanical & Materials Engineering, University College Dublin, Belfield, D04 V1W8 Dublin, Ireland
| | - Michael D Gilchrist
- School of Mechanical & Materials Engineering, University College Dublin, Belfield, D04 V1W8 Dublin, Ireland
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Buchberger G, Meyer M, Plamadeala C, Weissbach M, Hesser G, Baumgartner W, Heitz J, Joel AC. Robustness of antiadhesion between nanofibers and surfaces covered with nanoripples of varying spatial period. Front Ecol Evol 2023; 11:fevo.2023.1149051. [PMID: 37786452 PMCID: PMC7615146 DOI: 10.3389/fevo.2023.1149051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023] Open
Abstract
Since nanofibers have a high surface-to-volume ratio, van der Waals forces render them attracted to virtually any surface. The high ratio provides significant advantages for applications in drug delivery, wound healing, tissue regeneration, and filtration. Cribellate spiders integrate thousands of nanofibers into their capture threads as an adhesive to immobilize their prey. These spiders have antiadhesive nanoripples on the calamistrum, a comb-like structure on their hindmost legs, and are thus an ideal model for investigating how nanofiber adhesion can be reduced. We found that these nanoripples had similar spacing in the cribellate species Uloborus plumipes, Amaurobius similis, and Menneus superciliosus, independent of phylogenetic relation and size. Ripple spacing on other body parts (i.e., cuticle, claws, and spinnerets), however, was less homogeneous. To investigate whether a specific distance between the ripples determines antiadhesion, we fabricated nanorippled foils by nanosecond UV laser processing. We varied the spatial periods of the nanoripples in the range ~203-613 nm. Using two different pulse numbers resulted in ripples of different heights. The antiadhesion was measured for all surfaces, showing that the effect is robust against alterations across the whole range of spatial periods tested. Motivated by these results, we fabricated irregular surface nanoripples with spacing in the range ~130-480 nm, which showed the same antiadhesive behavior. The tested surfaces may be useful in tools for handling nanofibers such as spoolers for single nanofibers, conveyor belts for producing endless nanofiber nonwoven, and cylindrical tools for fabricating tubular nanofiber nonwoven. Engineered fibers such as carbon nanotubes represent a further candidate application area.
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Affiliation(s)
- Gerda Buchberger
- Institute of Applied Physics, Johannes Kepler University Linz, Linz, Austria
- Institute of Biomedical Mechatronics, Johannes Kepler University Linz, Linz, Austria
| | - Marco Meyer
- Institute for Biology II, RWTH Aachen University, Aachen, Germany
| | - Cristina Plamadeala
- Institute of Applied Physics, Johannes Kepler University Linz, Linz, Austria
| | | | - Günter Hesser
- Center for Surface and Nanoanalytics, Johannes Kepler University Linz, Linz, Austria
| | - Werner Baumgartner
- Institute of Biomedical Mechatronics, Johannes Kepler University Linz, Linz, Austria
| | - Johannes Heitz
- Institute of Applied Physics, Johannes Kepler University Linz, Linz, Austria
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8
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Heitz J. Nanopatterning of Bionic Materials. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13020233. [PMID: 36677985 PMCID: PMC9864547 DOI: 10.3390/nano13020233] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 12/23/2022] [Indexed: 05/27/2023]
Abstract
The nanopatterning of bionic materials, performed by means of laser processes that utilize pulsed laser sources with short and ultrashort pulse durations, is a rapidly growing field [...].
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Affiliation(s)
- Johannes Heitz
- Institute of Applied Physics, Johannes Kepler University Linz, Altenberger Strasse 69, 4040 Linz, Austria
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Maalouf M, Abou Khalil A, Di Maio Y, Papa S, Sedao X, Dalix E, Peyroche S, Guignandon A, Dumas V. Polarization of Femtosecond Laser for Titanium Alloy Nanopatterning Influences Osteoblastic Differentiation. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:1619. [PMID: 35630841 PMCID: PMC9147489 DOI: 10.3390/nano12101619] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/04/2022] [Accepted: 05/06/2022] [Indexed: 12/23/2022]
Abstract
Ultrashort pulse lasers have significant advantages over conventional continuous wave and long pulse lasers for the texturing of metallic surfaces, especially for nanoscale surface structure patterning. Furthermore, ultrafast laser beam polarization allows for the precise control of the spatial alignment of nanotextures imprinted on titanium-based implant surfaces. In this article, we report the biological effect of beam polarization on human mesenchymal stem cell differentiation. We created, on polished titanium-6aluminum-4vanadium (Ti-6Al-4V) plates, a laser-induced periodic surface structure (LIPSS) using linear or azimuthal polarization of infrared beams to generate linear or radial LIPSS, respectively. The main difference between the two surfaces was the microstructural anisotropy of the linear LIPSS and the isotropy of the radial LIPSS. At 7 d post seeding, cells on the radial LIPSS surface showed the highest extracellular fibronectin production. At 14 days, qRT-PCR showed on the same surface an increase in osteogenesis-related genes, such as alkaline phosphatase and osterix. At 21 d, mineralization clusters indicative of final osteoinduction were more abundant on the radial LIPSS. Taken together, we identified that creating more isotropic than linear surfaces enhances cell differentiation, resulting in an improved osseointegration. Thus, the fine tuning of ultrashort pulse lasers may be a promising new route for the functionalization of medical implants.
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Affiliation(s)
- Mathieu Maalouf
- SAINBIOSE Laboratory INSERM U1509, Jean Monnet University, University of Lyon, F-42270 Saint Priest en Jarez, France; (S.P.); (E.D.); (S.P.); (A.G.)
| | - Alain Abou Khalil
- Hubert-Curien Laboratory, Jean Monnet University, University of Lyon, UMR 5516 CNRS, F-42000 Saint-Etienne, France; (A.A.K.); (X.S.)
| | - Yoan Di Maio
- GIE Manutech-USD, F-42000 Saint-Etienne, France;
| | - Steve Papa
- SAINBIOSE Laboratory INSERM U1509, Jean Monnet University, University of Lyon, F-42270 Saint Priest en Jarez, France; (S.P.); (E.D.); (S.P.); (A.G.)
| | - Xxx Sedao
- Hubert-Curien Laboratory, Jean Monnet University, University of Lyon, UMR 5516 CNRS, F-42000 Saint-Etienne, France; (A.A.K.); (X.S.)
- GIE Manutech-USD, F-42000 Saint-Etienne, France;
| | - Elisa Dalix
- SAINBIOSE Laboratory INSERM U1509, Jean Monnet University, University of Lyon, F-42270 Saint Priest en Jarez, France; (S.P.); (E.D.); (S.P.); (A.G.)
| | - Sylvie Peyroche
- SAINBIOSE Laboratory INSERM U1509, Jean Monnet University, University of Lyon, F-42270 Saint Priest en Jarez, France; (S.P.); (E.D.); (S.P.); (A.G.)
| | - Alain Guignandon
- SAINBIOSE Laboratory INSERM U1509, Jean Monnet University, University of Lyon, F-42270 Saint Priest en Jarez, France; (S.P.); (E.D.); (S.P.); (A.G.)
| | - Virginie Dumas
- Laboratory of Tribology and Systems Dynamics, Ecole Nationale d’Ingénieurs de Saint Etienne, Ecole Centrale de Lyon, University of Lyon, UMR 5513 CNRS, F-42100 Saint-Etienne, France;
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Bonse J, Gräf S. Ten Open Questions about Laser-Induced Periodic Surface Structures. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:3326. [PMID: 34947674 PMCID: PMC8709363 DOI: 10.3390/nano11123326] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 11/30/2021] [Accepted: 12/04/2021] [Indexed: 12/04/2022]
Abstract
Laser-induced periodic surface structures (LIPSS) are a simple and robust route for the nanostructuring of solids that can create various surface functionalities featuring applications in optics, medicine, tribology, energy technologies, etc. While the current laser technologies already allow surface processing rates at the level of m2/min, industrial applications of LIPSS are sometimes hampered by the complex interplay between the nanoscale surface topography and the specific surface chemistry, as well as by limitations in controlling the processing of LIPSS and in the long-term stability of the created surface functions. This Perspective article aims to identify some open questions about LIPSS, discusses the pending technological limitations, and sketches the current state of theoretical modelling. Hereby, we intend to stimulate further research and developments in the field of LIPSS for overcoming these limitations and for supporting the transfer of the LIPSS technology into industry.
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Affiliation(s)
- Jörn Bonse
- Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, D-12205 Berlin, Germany
| | - Stephan Gräf
- Otto-Schott-Institut für Materialforschung (OSIM), Löbdergraben 32, D-07743 Jena, Germany
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Ambient Climate Influences Anti-Adhesion between Biomimetic Structured Foil and Nanofibers. NANOMATERIALS 2021; 11:nano11123222. [PMID: 34947571 PMCID: PMC8707556 DOI: 10.3390/nano11123222] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 11/10/2021] [Accepted: 11/24/2021] [Indexed: 01/16/2023]
Abstract
Due to their uniquely high surface-to-volume ratio, nanofibers are a desired material for various technical applications. However, this surface-to-volume ratio also makes processing difficult as van der Waals forces cause nanofibers to adhere to virtually any surface. The cribellate spider Uloborus plumipes represents a biomimetic paragon for this problem: these spiders integrate thousands of nanofibers into their adhesive capture threads. A comb on their hindmost legs, termed calamistrum, enables the spiders to process the nanofibers without adhering to them. This anti-adhesion is due to a rippled nanotopography on the calamistrum. Via laser-induced periodic surface structures (LIPSS), these nanostructures can be recreated on artificial surfaces, mimicking the non-stickiness of the calamistrum. In order to advance the technical implementation of these biomimetic structured foils, we investigated how climatic conditions influence the anti-adhesive performance of our surfaces. Although anti-adhesion worked well at low and high humidity, technical implementations should nevertheless be air-conditioned to regulate temperature: we observed no pronounced anti-adhesive effect at temperatures above 30 °C. This alteration between anti-adhesion and adhesion could be deployed as a temperature-sensitive switch, allowing to swap between sticking and not sticking to nanofibers. This would make handling even easier.
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