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This study is focused on polytetrafluoroethylene (PTFE) porous nanotextile and its modification with thin, silver sputtered nanolayers, combined with a subsequent modification with an excimer laser. The KrF excimer laser was set to single-shot pulse mode. Subsequently, the physico chemical properties, morphology, surface chemistry, and wettability were determined. Minor effects of the excimer laser on the pristine PTFE substrate were described, but significant changes were observed after the application of the excimer laser to the polytetrafluoroethylene with sputtered silver, where the formation of a silver nanoparticles/PTFE/Ag composite was described, with a wettability similar to that of a superhydrophobic surface. Both scanning electron microscopy and atomic force microscopy revealed the formation of superposed globular structures on the polytetrafluoroethylene lamellar primary structure, which was also confirmed using energy dispersive spectroscopy. The combined changes in the surface morphology, chemistry, and thus wettability induced a significant change in the PTFE's antibacterial properties. Samples coated with silver and further treated with the excimer laser 150 mJ/cm 2 inhibited 100% of the bacterial strain E. coli . The motivation of this study was to find a material with flexible and elastic properties and a hydrophobic character, with antibacterial properties that could be enhanced with silver nanoparticles, but hydrophobic properties that would be maintained. These properties can be used in different types of applications, mainly in tissue engineering and the medicinal industry, where water-repellent materials may play important roles. This synergy was achieved via the technique we proposed, and even when the Ag nanostructures were prepared, the high hydrophobicity of the system Ag-polytetrafluorethylene was maintained.

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.

The main aim of this study was to describe the treatment of carbon sheet with a high-energy excimer laser. The excimer modification changed the surface chemistry and morphology of carbon. The appearance of specific carbon forms and modifications have been detected due to exposure to laser beam fluencies up to 8 J cm -2 . High fluence optics was used for dramatic changes in the carbon layer with the possibility of Q-carbon formation; a specific amorphous carbon phase was detected with Raman spectroscopy. The changes in morphology were determined with atomic force microscopy and confirmed with scanning electron microscopy, where the partial formation of the Q-carbon phase was detected. Energy dispersive spectroscopy (EDS) was applied for a detailed study of surface chemistry. The particular shift of functional groups induced on laser-treated areas was determined by X-ray photoelectron spectroscopy. For the first time, high-dose laser exposure successfully induced a specific amorphous carbon phase.

A polydimethylsiloxane (PDMS) composite with multi-walled carbon nanotubes was successfully prepared. Composite foils were treated with both plasma and excimer laser, and changes in their physicochemical properties were determined in detail. Mainly changes in surface chemistry, wettability, and morphology were determined. The plasma treatment of PDMS complemented with subsequent heating led to the formation of a unique wrinkle-like pattern. The impact of different laser treatment conditions on the composite surface was determined. The morphology was determined by AFM and LCM techniques, while chemical changes and chemical surface mapping were studied with the EDS/EDX method. Selected activated polymer composites were used for the evaluation of antibacterial activity using Gram-positive ( Staphylococcus epidermidis ) and Gram-negative ( Escherichia coli ) bacteria. The antibacterial effect was achieved against S. epidermidis on pristine PDMS treated with 500 mJ of laser energy and PDMS-C nanocomposite treated with a lower laser fluence of 250 mJ. Silver deposition of PDMS foil increases significantly its antibacterial properties against E. coli , which is further enhanced by the carbon predeposition or high-energy laser treatment.

This study involved the preparation and characterization of structures with a honeycomb-like pattern (HCP) formed using the phase separation method using a solution mixture of chloroform and methanol together with cellulose acetate. Fluorinated ethylene propylene modified by plasma treatment was used as a suitable substrate for the formation of the HCP structures. Further, we modified the HCP structures using silver sputtering (discontinuous Ag nanoparticles) or by adding Ag nanoparticles in PEG into the cellulose acetate solution. The material morphology was then determined using atomic force microscopy (AFM) and scanning electron microscopy (SEM), while the material surface chemistry was studied using energy dispersive spectroscopy (EDS) and wettability was analyzed with goniometry. The AFM and SEM results revealed that the surface morphology of pristine HCP with hexagonal pores changed after additional sample modification with Ag, both via the addition of nanoparticles and sputtering, accompanied with an increase in the roughness of the PEG-doped samples, which was caused by the high molecular weight of PEG and its gel-like structure. The highest amount (approx. 25 at %) of fluorine was detected using the EDS method on the sample with an HCP-like structure, while the lowest amount (0.08%) was measured on the PEG + Ag sample, which revealed the covering of the substrate with biopolymer (the greater fluorine extent means more of the fluorinated substrate is exposed). As expected, the thickness of the Ag layer on the HCP surface depended on the length of sputtering (either 150 s or 500 s). The sputtering times for Ag (150 s and 500 s) corresponded to layers with heights of about 8 nm (3.9 at % of Ag) and 22 nm (10.8 at % of Ag), respectively. In addition, we evaluated the antibacterial potential of the prepared substrate using two bacterial strains, one Gram-positive of S. epidermidis and one Gram-negative of E. coli . The most effective method for the construction of antibacterial surfaces was determined to be sputtering (150 s) of a silver nanolayer onto a HCP-like cellulose structure, which proved to have excellent antibacterial properties against both G+ and G- bacterial strains.

We report on a novel technique of surface texturing of polyethylene terephthalate (PET) foil in the presence of silver nanoparticles (AgNPs). This approach provides a variable surface morphology of PET evenly decorated with AgNPs. Surface texturing occurred in silver nanoparticle colloids of different concentrations under the action of pulse excimer laser. Surface morphology of PET immobilized with AgNPs was observed by AFM and FEGSEM. Atomic concentration of silver was determined by XPS. A presented concentration-controlled procedure of surface texturing of PET in the presence of silver colloids leads to a highly nanoparticle-enriched polymer surface with a variable morphology and uniform nanoparticle distribution.

The development of new biocompatible polymer substrates is still of interest to many research teams. We aimed to combine a plasma treatment of fluorinated ethylene propylene (FEP) substrate with a technique of improved phase separation. Plasma exposure served for substrate activation and modification of surface properties, such as roughness, chemistry, and wettability. The treated FEP substrate was applied for the growth of a honeycomb-like pattern from polystyrene solution. The properties of the pattern strongly depended on the primary plasma exposure of the FEP substrate. The physico-chemical properties such as changes of the surface chemistry, wettability, and morphology of the prepared pattern were determined. The cell response of primary fibroblasts and osteoblasts was studied on a honeycomb pattern. The prepared honeycomb-like pattern from polystyrene showed an increase in cell viability and a positive effect on cell adhesion and proliferation for both primary fibroblasts and osteoblasts.

Homogeneous polystyrene foils doped with different concentrations of acetylsalicylic acid were prepared by the solvent casting method. The surface morphology and surface chemistry of as-prepared foils were characterized in detail. Excimer laser (krypton fluoride, a wavelength of 248 nm) was used for surface nanopatterning of doped polystyrene foils. Certain combinations of laser fluence and number of laser pulses led to formation of laser-induced periodic surface structures (LIPSS) on the exposed surface. Formation of the pattern was affected by the presence of a dopant in the polystyrene structure. Significant differences in surface chemistry and morphology of laser-treated foils compared to both pristine and doped polystyrene were detected. The pattern width and height were both affected by selection of input excimer exposure conditions, and the amount of 6000 pulses was determined as optimal. The possibility of nanostructuring of a honeycomb-like pattern doped with acetylsalicylic acid was also demonstrated. Selected nanostructured surfaces were used for study the antibacterial properties for a model bacteria strain of S. aureus . The combination of altered surface chemistry and morphology of polystyrene was confirmed to have an excellent antibacterial properties.

The versatile family of nanoparticles is considered to have a huge impact on the different fields of materials research, mostly nanoelectronics, catalytic chemistry and in study of cytocompatibility, targeted drug delivery and tissue engineering. Different approaches for nanoparticle preparation have been developed, not only based on "bottom up" and "top down" techniques, but also several procedures of effective nanoparticle modifications have been successfully used. This paper is focused on different techniques of nanoparticles' preparation, with primary focus on metal nanoparticles. Dispergation methods such as laser ablation and vacuum sputtering are introduced. Condensation methods such as reduction with sodium citrate, the Brust-Schiffrin method and approaches based on ultraviolet light or biosynthesis of silver and gold are also discussed. Basic properties of colloidal solutions are described. Also a historical overview of nanoparticles are briefly introduced together with short introduction to specific properties of nanoparticles and their solutions.

A laser induced periodic surface structure (LIPSS) on graphene doped polystyrene was prepared by the means of a krypton fluoride (KrF) laser with the wavelength of 248 nm and precisely desired physico-chemical properties were obtained for the structure. Surface morphology after laser modification of polystyrene (PS) doped with graphene nanoplatelets (GNP) was studied. Laser fluence values of modifying laser light varied between 0-40 mJ·cm -2 and were used on polymeric PS substrates doped with 10, 20, 30, and 40 wt. % of GNP. GNP were incorporated into PS substrate with the solvent casting method and further laser modification was achieved with the same amount of laser pulses of 6000. Formed nanostructures with a periodic pattern were examined by atomic force microscopy (AFM). The morphology was also studied with scanning electron microscopy SEM. Laser irradiation resulted in changes of chemical composition on the PS surface, such as growth of oxygen concentration. This was confirmed with energy-dispersive X-ray spectroscopy (EDS).

While polymers are widely utilized materials in the biomedical industry, they are rarely used in an unmodified state. Some kind of a surface treatment is often necessary to achieve properties suitable for specific applications. There are multiple methods of surface treatment, each with their own pros and cons, such as plasma and laser treatment, UV lamp modification, etching, grafting, metallization, ion sputtering and others. An appropriate treatment can change the physico-chemical properties of the surface of a polymer in a way that makes it attractive for a variety of biological compounds, or, on the contrary, makes the polymer exhibit antibacterial or cytotoxic properties, thus making the polymer usable in a variety of biomedical applications. This review examines four popular methods of polymer surface modification: laser treatment, ion implantation, plasma treatment and nanoparticle grafting. Surface treatment-induced changes of the physico-chemical properties, morphology, chemical composition and biocompatibility of a variety of polymer substrates are studied. Relevant biological methods are used to determine the influence of various surface treatments and grafting processes on the biocompatibility of the new surfaces-mammalian cell adhesion and proliferation is studied as well as other potential applications of the surface-treated polymer substrates in the biomedical industry., Competing Interests: The authors declare no conflict of interest.