The construction of functional micro- or nanostructured surfaces is extensively studied since they are able to provide multifunctional properties and for large variety of potential applications in fields such as tissue engineering, wearable electronics or microfluidics. The micro- or nanosized surfaces can be easily prepared by various lithography techniques, also additional modifications (laser exposure, metal deposition and further processing) and which can induce new applicable properties on the basis of synergic effect by combining aforementioned approaches. In this work we have focused on the polytetrafluoroethylene (PTFE) nanotextile with specific bimetallic nanostructures. Our primary target was to find optimal surface modification of silver/gold coated surface, which would induce strong antibacterial response to both gram-positive and/or gram-negative bacteria. We have used plasma-modified polytetrafluoroethylene nanotextile as a substrate, onto which silver and gold nanolayers were deposited by sputtering. The foils were further subjected to "single-shot" exposure to an excimer KrF laser and some samples were also thermally stressed before exposure. Such surfaces were further examined in terms of surface morphology and chemical composition. The surface was investigated for antibacterial properties. Their antimicrobial activity was examined in vitro against the bacteria Escherichia coli and Staphylococcus epidermidis strains. The surface of the prepared materials was replicated into a lactic acid polymer and the properties were again investigated in terms of surface morphology and surface chemistry. The results demonstrated construction of antibacterial surfaces with excellent resistance to bacteria E. coli for bimetallic structures on PTFE. Excimer laser induced bimetallic pattern exhibited also significant antibacterial properties for S. epidermidis. Replication of bimetallic pattern was also demonstrated.

• Keywords
• Antibacterial properties, Bimetallic nanopattern, Laser exposure, Nanostructure, Nanotextile, Noble metal, PTFE, Polymer, Replication,
• Publication type
• Journal Article MeSH

Here, we present surface analysis and biocompatibility evaluation of novel composite material based on graphene oxide traded as BioHastalex. The pristine material's surface morphology and surface chemistry were examined by various analytical methods. The BioHastalex with a thin silver layer was subsequently heat treated and characterized, the impact on the material surface wettability and morphology was evaluated. Significant surface roughness and morphology changes were detected at the nanometer scale after heat treatment of Ag-sputtered BioHastalex. The deposition of a thin silver nanolayer had an outstanding effect on BioHastalex's antibacterial properties while still maintaining cell viability (MRC-5, HaCaT). The heat treatment of BioHastalex-Ag led to the formation of regular nanocluster arrays while affecting the Ag concentration on the very surface. The decrease in silver concentration was connected with the length of heat treatment; cells growing on such samples exhibited good viability, and the antibacterial properties were weaker than simply sputtered BioHastalex.

• Keywords
• BioHastalex, Cytocompatibility, Graphene composite, Morphology, Nanostructure, Polymer stability, Surface chemistry, Surface modification,
• Publication type
• Journal Article MeSH

Here, we present surface analysis and biocompatibility evaluation of novel composite material based on graphene oxide traded as Hastalex. First, the surface morphology and elemental analysis of the pristine material were examined by atomic force and scanning electron microscopies, and by energy-dispersive and X-ray photoelectron spectroscopies, respectively. The Hastalex surface was then modified by plasma (3 and 8 W with exposure times up to 240 s), the impact of which on the material surface wettability and morphology was further evaluated. In addition, the material aging was studied at room and elevated temperatures. Significant changes in surface roughness, morphology, and area were detected at the nanometer scale after plasma exposure. An increase in oxygen content due to the plasma exposure was observed both for 3 and 8 W. The plasma treatment had an outstanding effect on the cytocompatibility of Hastalex foil treated at both input powers of 3 and 8 W. The cell number of human MRC-5 fibroblasts on Hastalex foils exposed to plasma increased significantly compared to pristine Hastalex and even to tissue culture polystyrene. The plasma exposure also affected the fibroblasts' cell growth and shape.

• Keywords
• Carbon composite, Cytocompatibility, Morphology, Nanostructure, Pattern, Polymer stability, Surface chemistry, Surface modification,
• Publication type
• Journal Article MeSH

We focused on polydimethylsiloxane (PDMS) as a substrate for replication, micropatterning, and construction of biologically active surfaces. The novelty of this study is based on the combination of the argon plasma exposure of a micropatterned PDMS scaffold, where the plasma served as a strong tool for subsequent grafting of collagen coatings and their application as cell growth scaffolds, where the standard was significantly exceeded. As part of the scaffold design, templates with a patterned microstructure of different dimensions (50 × 50, 50 × 20, and 30 × 30 μm2) were created by photolithography followed by pattern replication on a PDMS polymer substrate. Subsequently, the prepared microstructured PDMS replicas were coated with a type I collagen layer. The sample preparation was followed by the characterization of material surface properties using various analytical techniques, including scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). To evaluate the biocompatibility of the produced samples, we conducted studies on the interactions between selected polymer replicas and micro- and nanostructures and mammalian cells. Specifically, we utilized mouse myoblasts (C2C12), and our results demonstrate that we achieved excellent cell alignment in conjunction with the development of a cytocompatible surface. Consequently, the outcomes of this research contribute to an enhanced comprehension of surface properties and interactions between structured polymers and mammalian cells. The use of periodic microstructures has the potential to advance the creation of novel materials and scaffolds in tissue engineering. These materials exhibit exceptional biocompatibility and possess the capacity to promote cell adhesion and growth.

• Keywords
• PDMS, coating, collagen type I, cytocompatibility, microstructure, myoblast cell, nanostructured pattern, replication, soft lithography,
• MeSH
• Cell Adhesion MeSH
• Dimethylpolysiloxanes chemistry   MeSH
• Collagen * chemistry   MeSH
• Myoblasts MeSH
• Mice MeSH
• Surface Properties MeSH
• Mammals MeSH
• Tissue Engineering * MeSH
• Animals MeSH
• Check Tag
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Dimethylpolysiloxanes MeSH
• Collagen * MeSH

In this review, we present a comprehensive summary of the formation of honeycomb microstructures and their applications, which include tissue engineering, antibacterial materials, replication processes or sensors. The history of the honeycomb pattern, the first experiments, which mostly involved the breath figure procedure and the improved phase separation, the most recent approach to honeycomb pattern formation, are described in detail. Subsequent surface modifications of the pattern, which involve physical and chemical modifications and further enhancement of the surface properties, are also introduced. Different aspects influencing the polymer formation, such as the substrate influence, a particular polymer or solvent, which may significantly contribute to pattern formation, and thus influence the target structural properties, are also discussed.

• Keywords
• antibacterial properties, biopolymer, breath figure, honeycomb, improved phase separation, morphology, polymer, replication, surface modification, tissue engineering,
• Publication type
• Journal Article MeSH
• Review MeSH

Metal nanostructure-treated polymers are widely recognized as the key material responsible for a specific antibacterial response in medical-based applications. However, the finding of an optimal bactericidal effect in combination with an acceptable level of cytotoxicity, which is typical for metal nanostructures, prevents their expansion from being more significant so far. This study explores the possibility of firmly anchoring silver nanoparticles (AgNPs) into polyetherether ketone (PEEK) with a tailored surface morphology that exhibits laser-induced periodic surface structures (LIPSS). We demonstrated that laser-induced forward transfer technology is a suitable tool, which, under specific conditions, enables uniform decoration of the PEEK surface with AgNPs, regardless of whether the surface is planar or LIPSS structured. The antibacterial test proved that AgNPs-decorated LIPSS represents a more effective bactericidal protection than their planar counterparts, even if they contain a lower concentration of immobilized particles. Nanostructured PEEK with embedded AgNPs may open up new possibilities in the production of templates for replication processes in the construction of functional bactericidal biopolymers or may be directly used in tissue engineering applications.

• Keywords
• bactericidal effect, laser treatment, periodic structures, silver nanoparticles, surface morphology,
• MeSH
• Anti-Bacterial Agents pharmacology   chemistry   MeSH
• Ketones chemistry   MeSH
• Metal Nanoparticles * chemistry   MeSH
• Polyethylene Glycols chemistry   MeSH
• Silver chemistry   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Anti-Bacterial Agents MeSH
• Ketones MeSH
• polyetheretherketone MeSH Browser
• Polyethylene Glycols MeSH
• Silver MeSH

In this article, we present a unique combination of techniques focusing on the immobilization of noble metal nanoparticles into a honeycomb polystyrene pattern prepared with the improved phase-separation technique. The procedure consists of two main steps: the preparation of the honeycomb pattern (HCP) on a perfluoroethylenepropylene substrate (FEP), followed by an immobilization procedure realized by the honeycomb pattern's exposure to an excimer laser in a noble metal nanoparticle solution. The surface physico-chemical properties, mainly the surface morphology and chemistry, are characterized in detail in the study. The two-step procedure represents the unique architecture of the surface immobilization process, which reveals a wide range of potential applications, mainly in tissue engineering, but also as substrates for analytical use.

• Keywords
• excimer laser, gold nanocluster, honeycomb, immobilization, morphology, nanostructure, polystyrene,
• Publication type
• Journal Article MeSH

Design and properties of a plasmonic modulator in situ tunable by electric field are presented. Our design comprises the creation of periodic surface pattern on the surface of an elastic polymer supported by a piezo-substrate by excimer laser irradiation and subsequent selective coverage by silver by tilted angle vacuum evaporation. The structure creation was confirmed by AFM and FIB-SEM techniques. An external electric field is used for fine control of the polymer pattern amplitude, which tends to decrease with increasing voltage. As a result, surface plasmon-polariton excitation is quenched, leading to the less pronounced structure of plasmon response. This quenching was checked using UV-Vis spectroscopy and SERS measurements, and confirmed by numerical simulation. All methods prove the proposed functionality of the structures enabling the creation smart plasmonic materials for a very broad range of advanced optical applications.

• Keywords
• LIPSS, SERS, modification, nanostructures, plasmon excitation, polymer, sensor, smart materials, thin layers,
• Publication type
• Journal Article MeSH

Biomimicking native tissues and organs require the development of advanced hydrogels. The patterning of hydrogel surfaces may enhance the cellular functionality and therapeutic efficacy of implants. For example, nanopatterning of the intraocular lens (IOL) surface can suppress the upregulation of cytoskeleton proteins (actin and actinin) within the cells in contact with the IOL surface and, hence, prevent secondary cataracts causing blurry or opaque vision. Here we introduce a fast and efficient method for fabricating arrays consisting of millions of individual nanostructures on the hydrogel surface. In particular, we have prepared the randomly distributed nanopillars on poly(2-hydroxyethyl methacrylate) hydrogel using replica molding and show that the number, shape, and arrangement of nanostructures are fully adjustable. Characterization by atomic force microscopy revealed that all nanopillars were of similar shape, narrow size distribution, and without significant defects. In imprint lithography, choosing the appropriate hydrogel composition is critical. As hydrogels with imprinted nanostructures mimic the natural cell environment, they can find applications in fundamental cell biology research, e.g., they can tune cell attachment and inhibit or promote cell clustering by a specific arrangement of protrusive nanostructures on the hydrogel surface.

• MeSH
• Hydrogels chemistry   MeSH
• Microscopy, Atomic Force MeSH
• Nanostructures * chemistry   MeSH
• Hydrogel, Polyethylene Glycol Dimethacrylate chemistry   MeSH
• Polyhydroxyethyl Methacrylate * chemistry   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Hydrogels MeSH
• Hydrogel, Polyethylene Glycol Dimethacrylate MeSH
• Polyhydroxyethyl Methacrylate * MeSH

Here, we aimed at the preparation of an antibacterial surface on a flexible polydimethylsiloxane substrate. The polydimethylsiloxane surface was sputtered with silver, deposited with carbon, heat treated and exposed to excimer laser, and the combinations of these steps were studied. Our main aim was to find the combination of techniques applicable both against Gram-positive and Gram-negative bacteria. The surface morphology of the structures was determined by atomic force microscopy and scanning electron microscopy. Changes in surface chemistry were conducted by application of X-ray photoelectron spectroscopy and energy dispersive spectroscopy. The changes in surface wettability were characterized by surface free energy determination. The heat treatment was also applied to selected samples to study the influence of the process on layer stability and formation of PDMS-Ag or PDMS-C-Ag composite layer. Plasmon resonance effect was determined for as-sputtered and heat-treated Ag on polydimethylsiloxane. The heating of such structures may induce formation of a pattern with a surface plasmon resonance effect, which may also significantly affect the antibacterial activity. We have implemented sputtering of the carbon base layer in combination with excimer laser exposure of PDMS/C/Ag to modify its properties. We have confirmed that deposition of primary carbon layer on PDMS, followed by sputtering of silver combined with subsequent heat treatment and activation of such surface with excimer laser, led to the formation of a surface with strong antibacterial properties against two bacterial strains of S. epidermidis and E. coli.

• Keywords
• antibacterial properties, carbon, excimer laser, nanostructure, plasmon resonance, silver nanoclusters,
• Publication type
• Journal Article MeSH