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Here, we report poly(N-acryloylglycinamide-co-vinyltriazole) p(NAGA-co-VTZ) supramolecular polymer hydrogel doped with activated polypyrrole nanotubes (acPPyNTs) as a high-strength self-healable material for supercapacitors. First, the p(NAGA-co-VTZ) hydrogel films were synthesized by photopolymerization of N-acryloylglycinamide and 1-vinyl-1,2,4-triazole without any cross-linkers. Scanning electron microscopy and mechanical tests showed that initial monomer concentration strongly affects both hydrogel microstructure and resulted mechanical properties. The hydrogels demonstrated self-healing ability through hydrogen bonding at the temperatures above upper critical solubility temperature, excellent mechanical properties (0.9 MPa), large stretchability (1300 %) and cut resistance. Next, as active material for electrochemical double layer capacitors (EDLC) carbonized and ethanol/KOH activated polypyrrole nanotubes (acPPyNTs) were prepared. Symmetric self-healable supercapacitor employing p(NAGA-co-VTZ) hydrogel, acPPyNTs and aqueous 3M KCl solution was assembled. Cyclic voltammetry, galvanostatic charge-discharge measurements showed that the prepared device gave a specific capacitance of 282.62 F g-1 at 0.2 A g-1 and high areal capacitance of 316.86 mF cm-2 at scan rate of 10 mV s-1. The supercapacitor operates over wide voltage window (0-1.2 V) and provides excellent cyclic performance with capacitance retention of 97 % after 10 000 cycles and 94 % after self-healing. Overall, the prepared self-healable supercapacitor appears to have considerable potential as high-performance energy storage device., Comment: 17 pages, 5 figures, 1 table

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 nanometre 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.

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 combina-tion of argon plasma exposure of micropatterned PDMS scaffold, where the plasma served as a strong tool for subsequent grafting of collagen coating and their application as cell growth scaf-folds, where the standard has been significantly exceeded. As part of scaffold design, templates with a patterned microstructure of different dimensions (50 x 50, 50 x 20 and 30 x 30 microns 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 through 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 with micro- and nanostructures and mammalian cells. Specif-ically, 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 holds the potential for advancing 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.

The presented study highlights the efficiency of employing a KrF excimer laser to create diverse types of periodic nanostructures (LIPSS - laser induced periodic surface structures) on polyether ether ketone (PEEK) and polyethylene naphthalate (PEN) substrates. By exposing the polymer films below their ablation threshold to laser fluence ranging from 4 to 16 mJcm-2 at 6,000 pulses, we studied both single-phase exposure at beam incidence angles of 0deg and 45deg, and two-phase exposure. Atomic force microscopy analysis revealed that the laser-treated samples contained distinctive periodic patterns such as waves, globules, and pod-like structures each exhibiting unique surface roughness. Moreover, using analytical methods like EDS and XPS shed light on the changes in the atomic composition, specifically focusing on the C and O elements, as a result of laser exposure. Notably, in almost all cases, we observed an increase in oxygen percentage on the sample surfaces. This increase not only led to a decrease in the contact angle with water but also lowered the zeta potential value, thus showing that the modified samples have enhanced hydrophilicity of the surface and altered electrostatic properties. Last but not least, the samples were assessed for biocompatibility; we studied the interaction of the prepared replicates with mouse myoblasts (C2C12). The impact of globular/dot structures on the cell growth in comparison to pristine or linear LIPSS-patterned surfaces was determined. The linear pattern (LIPSS) induced the myoblast cell alignment along the pattern direction, while dot/globular pattern even enhanced the cytocompatibility compared to LIPSS samples.

The urgent need for sustainable and innovative approaches to mitigate the increasing levels of atmospheric CO$_2$ necessitates the development of efficient methods for its removal. In this study, we focus on the synthesis and functionalization of metal-organic framework (MOF) ZIF-8 at room temperature to enhance its capacity for CO$_2$ capture. Specifically, we investigated the impact of four amino-compounds, namely tetraethylenepentamine (TEPA), hexadecylamine (HDA), ethanolamine (ELA), and cyclopropylamine (CPA), on the chemical structure, size, surface area and porosity and CO$_2$ capturing of ZIF-8 powder. By varying concentrations of the amino-compounds, we examined their influence on the ZIF-8 properties. These results highlight the potential of simple synthesis and functionalization techniques for MOFs in enhancing their CO$_2$ capture capabilities. The findings from this study offer new opportunities for the development of strategies to mitigate CO$_2$ emissions using MOFs.

Chiral nanophotonic platforms provide a means of creating near fields with both enhanced asymmetric properties and intensities. They can be exploited for optical measurements that allow enantiomeric discrimination at detection levels greater than 6 orders of magnitude than is achieved with conventional chirally sensitive spectroscopic methods based on circularly polarized light. The optimal approach for exploiting nanophotonic platforms for chiral detection would be to use spectroscopic methods that provide a local probe of changes in the near field environment induced by the presence of chiral species. Here we show that surface enhanced Raman spectroscopy (SERS) is such a local probe of the near field environment. We have used it to achieve enantiomeric discrimination of chiral helicoid nanoparticles deposited on left and right-handed enantiomorphs of a chiral metafilm. Hotter electromagnetic hotspots are created for matched combinations of helicoid and metafilms (left-left and right-right), while mismatched combinations leads to significantly cooler electromagnetic hotspots. This large enantiomeric dependency on hotspot intensity is readily detected using SERS with the aid of an achiral Raman reporter molecule. In effect we have used SERS to distinguish between the different EM environments of the plasmonic diastereomers produced by mixing chiral nanoparticles and metafilms. The work demonstrates that by combining chiral nanophotonic platforms with established SERS strategies new avenues in ultrasensitive chiral detection can be opened.

Detection of enantiomers is a challenging problem in drug development as well as environmental and food quality monitoring where traditional optical detection methods suffer from low signals and sensitivity. Application of surface enhanced Raman scattering (SERS) for enantiomeric discrimination is a powerful approach for the analysis of optically active small organic or large biomolecules. In this work, for enantio-selective sensing we proposed the coupling of disposable chiral plasmonic shurikens supporting the chiral near-field distribution with SERS active silver nanoclusters. As a result of the plasmonic coupling significant difference in SERS response of optically active analytes is observed. This is hypothesized and confirmed by numerical simulations to be a consequence of the silver particles being excited by superchiral fields generated at the surface or the probe molecules achieving additional polarization. The plasmon coupling phenomena was found to be extremely sensitive to slight variations in shuriken geometry, silver nanostructured layer parameters, and SERS excitation wavelength(s). Designed structures were able to discriminate cysteine enantiomers at concentrations in the nanomolar range and probe biomolecular chirality, using a common Raman spectrometer within several minutes. The combination of disposable plasmonic substrates with specific near-field polarization can make the SERS enantiomer discrimination a commonly available technique using standard Raman spectrometers.