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Supercapacitors are at the forefront of energy storage innovation, offering a safer, more environmentally friendly alternative to traditional energy storage devices. With their rapid charge-discharge capabilities and exceptional cycle life, supercapacitors are revolutionizing the way we think about efficient and sustainable energy storage. In contrast to typical supercapacitor electrodes made of pure carbon materials, the introduction of heteroatoms through doping (such as nitrogen, oxygen, boron, fluorine, etc.) has been associated with accelerated charge transfer rates and additional pseudocapacitance. Research indicates that nitrogen, for example, can modify the electronic structure of carbon materials, ultimately enhancing their ability to store charge [1,2]. In this context, we unveil a novel electrode material: adenine-derived nitrogen- doped carbon nanofibers (NCNFs) tailored for high-performance aqueous supercapacitors. This study explores in-depth how nitrogen functional groups influence energy storage efficiency in aqueous electrolytes. Various materials were produced through electrospinning followed by stabilization/carbonization, utilizing adenine as a cost-effective nitrogen source. The nitrogen content was successfully controlled by varying adenine ratio, resulting in a unique nanostructure with notable nitrogen doping levels, reaching as high as 10.9% as determined by X-ray photoelectron spectroscopy (XPS). The uniform distribution of present chemical elements (carbon, nitrogen and oxygen) was revealed by high–angle annular dark field scanning transmission electron microscopy (HAADF-STEM) micrographs with energy dispersive X-ray spectroscopy (EDS) maps (Figure 1). The NCNFs exhibited high specific capacitance and cycle stability in various electrolytes, outperforming conventional carbon nanofibers. Through comprehensive electrochemical testing, including cyclic voltammetry and galvanostatic charge-discharge measurements, electrodes demonstrated a spec

Tungsten disulfide (WS2) nanoparticles have been extensively investigated in the biomedical field as theranostics due to their specific properties, including good biocompatibility. However, almost nothing is known about their effect on the immune system. This study aimed to investigate the effects of inorganic fullerene-like WS2 (IF- WS2) nanostructures on the immune response in vitro.

The shift towards low-carbon technologies is driving an increasing demand for energy conversion and storage systems like supercapacitors, batteries and fuel cells. Therefore, it is crucial to replace traditional materials with renewable and high-performance alternatives. This research introduces a novel approach of designing and fabricating high-performance conductive separators for supercapacitors, leveraging the interaction between alkali ions and highly crystalline nanocellulose (CNC), the most abundant biopolymer. The modified CNC with potassium ions exhibits exceptional performance, surpassing commercial glass microfiber separators in terms of mechanical properties and ionic conductivity. The hydrophilicity and high porosity facilitate efficient potassium ion transport, as demonstrated in supercapacitor devices. By integrating rehydrated conductive separators between glucose-derived mesoporous carbon electrodes, the supercapacitor device achieves high specific capacitance of 80 F/g at 10 mV/s in Swagelok cells and capacitance retention of 95% over 1000 consecutive cycles. These results highlight the potential of these innovative materials to serve as safe and high-performance components in renewable energy storage devices.

Poly(methyl methacrylate) (PMMA) for dental application offers advantages such as ease of fabrication, cost-effectiveness, and favorable physical and mechanical properties. However, these characteristics alone do not provide sufficient impact strength and hardness. As a result, pure PMMA is less suitable for dental applications. This research aimed to enhance the impact resistance and hardness of PMMA by incorporating hybrid nanoparticles based on SrTiO3 (STO). Field emission scanning microscopy was used for the identification of agglomerates in the composites, as well as for the determination of toughening mechanisms at the fracture surface. Various toughening mechanisms were observed, with crack pinning being dominant. Differential scanning calorimetry was conducted to study the influence of nanoparticles on the glass transition temperature (Tg) of PMMA. It was established that there was no significant influence on Tg. Mechanical property investigations revealed that the STO-based hybrid reinforcements significantly improved microhardness and total absorbed impact energy. The results of this study highlight the reinforcing potential of hybrid nanoparticles, suggesting that their application does not have to be limited to PMMA.

There is a great potential to use electrospun nanofibers and 3D-printed structures as drug carriers for biomedical applications, due to the possibility of delivering drugs at a controlled rate over some time at the site of action.

In this study, scaffolds based on natural polymer gelatin A, blended with polyvinylpyrrolidone were crosslinked by genipin (0.5and 1 wt%), in order to investigate their mechanical performance and potential for biomedical application. Semi-solid extrusion(SSE) 3D printing technique was used, enabling in situ crosslinking of the blend during processing. Swelling test showed that theswelling ratio reduces with higher concentration of genipin due to an increased crosslinking. The FTIR analysis confirmed thecrosslinking of scaffolds by genipin. DSC analysis and mechanical testing have shown improved thermal and mechanical properties. Morphological analysis of scaffolds by FESEM showed increased toughening of the material with the crosslinking. Tensilestrength and microhardness showed a significant rise in scaffolds with the increase in genipin content, which was up to 93.8%and 125.3%, respectively. These findings were in accordance with morphological features present in samples. The biological effect of the scaffold matrix system was evaluated by qualitative and quantitative cytotoxicity assessment in vitro, demonstratingthe absence of cytotoxicity in tested preparations in a direct test. The cytotoxicity index based on the metabolic activity of cells inan indirect test showed up to 20% reduction of viability compared with the control, confirming the absence of cytotoxicity, whichwas additionally verified by propidium iodine staining of the cells exposed to scaffolds. The presented gelatin-based crosslinkedscaffolds obtained by 3D printing represent good candidates for biomedical application and future research that includes furtherin vitro and in vivo analysis.

Due to the high use and misuse of antibiotics over the years, microbes have developed resistance to a significant number of drugs (so-called antimicrobial resistance - AMR) [1]. Therefore, the necessity for the development of natural antimicrobial agents to overcome growing bacterial resistance against synthetic antibiotics has been recognized. Thymol is a natural monoterpenoid, with proven anti-inflammatory, antioxidant, and antimicrobial properties and it has been recognized as safe by the FDA (it has GRAS status). With the aim to fabricate material with antibacterial activity, supercritical solvent impregnation (SSI) was applied for loading of commercial PLA-based absorbable surgical sutures with thymol in a green medium, supercritical CO2. Operating temperature and pressure were set to 35 °C and 10 MPa, while contact time was varied between 1 and 6 h. The SSI process was performed under mild processing parameters to obtain an effective amount of loaded thymol against tested bacteria keeping in mind the recommended safe content of thymol for human blood cells (in terms of cytotoxicity and mutagen effect) [2]. Selected process conditions enabled thymol loadings of 3.9–5.6% (Fig. 1) [3]. SEM analyses was used to monitor sutures' morphological change from swelling to agglutination induced by the increased amount of thymol in the material. ...

The objective of this study was to processand evaluatea suitablescaffold matrix system for drug delivery and tissue regeneration. Abioinspired approachwas applied.Thescaffold based onnatural polymer gelatin,blended with polyvinylpyrrolidone,and crosslinked by genipin,was 3D printed by semi-solid extrusion(SSE).This 3D printing techniquedoes not require high temperature or UV curing, so it allows the use ofthermo-and UV-sensitive drugs, cells, or other biological components.The influence of genipin, a natural crosslinking agent, and itscontent on the mechanical properties and the cytotoxicity of obtained scaffolds were investigated.

Porozni materijali na bazi čistih ugljeničnih nanovlakana i kompozita ugljeničnih nanovlakana i spinela prelaznih metala, dobijeni jednostavnim metodama procesiranja, ispitani su kao elektrode u superkondenzatorima. Procene skladištenja električne energije čistih ugljeničnih nanovlakana su izvršene u uređajima sa simetričnom konfiguracijom gde su dobijene maksimalne vrednosti kapacitivnosti i gustine energije od 183 F g–1 i 4,1 Wh kg–1, respektivno. Ove vrednosti su posledica specifične mezoporozne strukture koja omogućava olakšanu difuziju jona i visoke električne provodljivosti nanovlakana. Postignuta je i odlična stabilnost kapacitivnog učinka svih ugljeničnih elektroda od preko 95% nakon 5000 ciklusa punjenja/pražnjenja. Ovakvi rezultati ukazuju na moguću praktičnu primenu ugljeničnih nanovlakana u superkondenzatorima. Ugljenična nanovlakna su se pokazala i kao veoma atraktivna podloga za kombinovanje sa mešovitim kobalt–mangan spinelima. Fazni sastav nanokristala spinela, sa procenjenim srednjim prečnikom od oko 13 do 60 nm, uspešno je kontrolisan variranjem odnosa metalnih prekursora u procesu elektropredenja. Kompozitna nanovlakna u alkalnoj sredini se ponašaju kao materijali sa baterijskim karakteristikama i imaju visoke vrednosti kapaciteta do 68,5 mAh g–1. Testiranjem samonosivih kompozitnih elektroda u simetričnim uređajima dobijene su visoke vrednosti kapacitivnosti i do 384 F g–1. Postignuta je i odlična stabilnost učinka sa preko 95% svih ispitanih elektroda. Superiorna gustina energije od 11,5 Wh kg–1 pri niskim brzinama promene potencijala, i superiorna gustina električne snage od 2,6 kW kg–1 je uporediva sa komercijalno dostupnim superkondenzatorima, što ima značajne implikacije na praktično skladištenje električne energije putem novih materijala., Porous materials based on neat carbon nanofibers and composites of carbon nanofibers and transition metal spinels, produced by simple processing methods, were tested as electrodes in supercapacitors. The estimation of energy storage of neat carbon nanofibers were performed in devices with symmetrical configuration with maximum capacitance and energy density values for carbon nanofibers of 183 F g–1 and 4.1 Wh kg–1, respectively. These values are a consequence of the specific mesoporous structure that enables facile diffusion of ions and high electrical conductivity of nanofibers. Excellent stability of the capacitive performance of all carbon electrodes of over 95% was achieved after 5000 charge/discharge cycles. These results indicate the possible practical application of carbon nanofibers in supercapacitors. Carbon nanofibers have also proven to be a very attractive substrate to combine with mixed cobalt-manganese spinels. The phase composition of spinel nanocrystals, with an estimated diameter of about 13 to 60 nm, has been successfully controlled by varying the ratio of metal precursors in the electrospinning process. Composite nanofibers in alkaline environment behave like materials with battery characteristics and have high values of capacity up to 68.5 mAh g–1. By testing self-supporting composite electrodes in symmetric devices, high capacitance values up to 384 F g–1 were obtained. Excellent stability was achieved with over 95% of all tested electrodes. The superior energy density of 11.5 Wh kg–1 at low potential sweep rates, and the superior power density of 2.6 kW kg–1 are comparable to commercially available supercapacitors, which has significant implications for the practical electrical energy storage through new materials.

We reported the putative beneficial effect of Trichinella spiralis infection in autoimmune encephalomyelitis—EAE, as animal model of human chronic inflammatory disease – multiple sclerosis.

In this study, polycaprolactone (PCL), as a biocompatible polymer was functionalized by addition of medicinal plant extract- Achillea millefolium L. (yarrow). Nanofiber mats were fabricated from PCL solutions containing dry yarrow extract in four concentrations (5%, 10%, 15%, and 20% relative to the weight of the polymer) by using blend electrospinning method. The nanofibers were characterized for their biological, mechanical and drug release behavior. In vitro release of yarrow polyphenols from the electrospun PCL nanofibers over a period of 5 days showed the release of up to 98% of the total loaded polyphenols. The released polyphenols retained its antioxidant activity, which was determined by DPPH assay. Electrospun PCL/yarrow nanofiber mats exhibited the antibacterial effect against Staphylococcus aureus, but had no effect on the growth of Pseudomonas aeruginosa. All PCL/yarrow nanofiber mats had improved mechanical properties compared to the neat PCL nanofibers, as evident by an increase in Young's modulus of elasticity (up to 5.7 times), the tensile strength (up to 5.5 times), and the strain at break (up to 1.45 times). Based on our results, yarrow-loaded PCL nanofiber mats appeared to be multi-functional biomaterials suitable for the production of catheter-coating materials, patches, or gauzes with antibacterial and antioxidant properties.

Biodegradable mulch films from cellulose (CELL), cellulose/polycaprolactone (CELL/PCL), cellulose/polycaprolactone/keratin (CELL/PCL/KER) and cellulose/polycaprolactone/keratin/ground calcium carbonate (CELL/PCL/KER/GCC) were prepared using Ionic liquid as a green solvent. Pure cellulose biopolymer is characterised by better mechanical properties (tensile strength - force per unit cross-sectional area at breakage - of 75.3 MPa and modulus of elasticity of 944.4 MPa) than the other studied samples which is attributed to the formation of partially miscible polymer blends. Among samples containing PCL, CELL/PCL/KER/GCC has the highest tensile strength and modulus of elasticity. The addition of KER or KER/GCC to CELL/PCL films resulted in an increment in melting temperature and an improvement of sample crystallinity. The light transmittance of all films was >60 %. The incorporation of KER enhanced the biodegradability of the biocomposites, while KER/GCC addition slightly inhibited degradation due to an increased hydrophobicity and crystallisation growth of semi-crystalline biopolymers. The reported method for mulch film preparation is green and recyclable, and, when including a readily available source of KER, such as by extraction from waste chicken feathers, enables conversion to organic biofertiliser. The findings of this study contributed to sustainable agriculture by providing nutrients that enhance the growth speed of the plant, and hence food production, and reduce environmental pressure. Inclusion of GCC additionally provides not only Ca2+ for plant consumption but also soil pH control.

Cellulose as the most abundant natural polymer holds great potential as a raw material for the preparation of both sustainable and economically viable polymeric products hitherto predominantly produced from synthetic fossil-based polymers. However, the utilization of cellulose to its full potential is constrained by its recalcitrance to chemical processing. Prior to processing and conversion into valuable products, cellulose needs to be dissolved and then regenerated via an efficient, energy-saving, and environmentally benign route. In the late 1990s, ionic liquids (ILs)have been re-discovered as the most promising cellulose solvents. The application of these novel, green solvents is discussed in detail. The subsequent regeneration of cellulose solutions from these solvents into various products such as fibers, films, membranes, beads, aerogels, hydrogels, and composites including all-cellulose composites, as well as their application in biomedicine, sorption, agriculture, packaging, and thermal insulation, have been reviewed. The properties of the regenerated cellulose material can be additionally tuned by the proper choice of the experimental conditions such as temperature and polarity of the coagulation medium. Furthermore, recycling and converting waste paper and cardboard into high-value materials have been discussed. The recyclability of ILs is one of the challenges to making the process cost-effective and environmentally benignthat scientists and technologists dealing with cellulose processing need to solve., Celuloza kao najzastupljeniji prirodni polimer ima veliki potencijal kao sirovina za proizvodnju kako održivih tako i ekonomski isplativih polimernih proizvoda koji su se do sada pretežno proizvodili od sintetičkih polimera na bazi petrohemijskih sirovina. Međutim, korišćenje celuloze u njenom punom potencijalu je ograničeno njenom otpornošću na hemijske tretmane. Pre obrade i konverzije u vredne proizvode, celulozu treba rastvoriti, a zatim regenerisati efikasnim, energetski štedljivim i ekološki benignim putem. Krajem 1990-ih, jonske tečnosti (ILs) su ponovo otkrivene kao najperspektivniji rastvarači celuloze. U radu je detaljno razmatrana primena ovih novih, zelenih rastvarača, kao i regeneracija celuloze rastvorene u jonskim tečnostima u različite proizvode kao što su vlakna, filmovi, membrane, sfere, aerogelovi, hidrogelovi i kompoziti, uključujući i kompozite celuloza-celuloza, i primena ovih proizvoda u biomedicini, poljoprivredi, kao sorbenata, ambalažnih i termoizolacionih materijala i sl. Svojstva regenerisanih celuloznih materijala mogu se dodatno podesiti pravilnim izborom eksperimentalnih uslova procesa regeneracije kao što su temperatura i polaritet medijuma za koagulaciju. Nadalje, analizirana je mogućnost recikliranja i pretvaranja starog papira i kartona u materijale visoke vrednosti. Reciklabilnost ILs je jedan od izazova koji naučnici i tehnolozi koji se bave preradom celuloze moraju da reše kako bi se proces učinio isplativim i ekološki benignim.

Ogromne količine celuloznog otpada (tekstila, papira i kartona), pri čemu se većina spaljuje ili završava na deponijama, dovode do ozbiljnog zagađenja životne sredine i značajnog rasipanja prirodnih resursa. Stoga je neophodna reciklaža/konverzija ovog celuloznog otpada u proizvode sa dodatom vrednošću. U tom kontekstu, celulozu treba rastvoriti i zatim regenerisati u različite proizvode (vlakna, filmove, membrane, mikro i nano sfere, aerogelove, hidrogelove i kompozite, uključujući i kompozite celuloza-celuloza) efikasnim, enegetski štedljivim i ekoliški benignim putem. U radu je analizirana sposobnost jonskih tečnosti da rastvaraju celulozu i naknadna regeneracija celuloze iz ovih rastvora u različite proizvode, kao i primena ovih proizvoda., Huge production of cellulose wastes (textiles, paper and cardboard) with most of them incinerated and landfilled, leads to seriously environmental pollution and significant waste of natural resources. Hence, recycling/conversion of these cellulose wastes into value-added products is urgent. In this context, cellulose needs to be dissolved and then regenerated into various products (fibers, films, membranes, beads, aerogels, hydrogels, and composites including all-cellulose composites) via en efficient, energy-saving, and environmentally benign route. The ability if ionic liquids to dissolve cellulose and the subsequent regeration of cellulose from these solutions into various products, as well as their application have been discussed.

Ionic liquid 1-butyl-3-methylimidazolium chloride [BMIM][Cl] was used to prepare cellulose (CELL), cellulose/polycaprolactone (CELL/PCL), cellulose/polycaprolactone/keratin (CELL/PCL/KER), and cellulose/polycaprolactone/keratin/ground calcium carbonate (CELL/PCL/KER/GCC) biodegradable mulch films. Attenuated Total Reflectance Fourier-Transform Infrared (ATR-FTIR) spectroscopy, optical microscopy, and Field-Emission Scanning Electron Microscopy (FE-SEM) were used to verify the films’ surface chemistry and morphology. Mulch film made of only cellulose regenerated from ionic liquid solution exhibited the highest tensile strength (75.3 ± 2.1 MPa) and modulus of elasticity of 944.4 ± 2.0 MPa. Among samples containing PCL, CELL/PCL/KER/GCC is characterized by the highest tensile strength (15.8 ± 0.4 MPa) and modulus of elasticity (687.5 ± 16.6 MPa). The film’s breaking strain decreased for all samples containing PCL upon the addition of KER and KER/GCC. The melting temperature of pure PCL is 62.3 °C, whereas that of CELL/PCL film has a slight tendency for melting point depression (61.0 °C), which is a characteristic of partially miscible polymer blends. Furthermore, Differential Scanning Calorimetry (DSC) analysis revealed that the addition of KER or KER/GCC to CELL/PCL films resulted in an increment in melting temperature from 61.0 to 62.6 and 68.9 °C and an improvement in sample crystallinity by 2.2 and 3.0 times, respectively. The light transmittance of all studied samples was greater than 60%. The reported method for mulch film preparation is green and recyclable ([BMIM][Cl] can be recovered), and the inclusion of KER derived by extraction from waste chicken feathers enables conversion to organic biofertilizer. The findings of this study contribute to sustainable agriculture by providing nutrients that enhance the growth rate of plants, and hence food production, while reducing environmental pressure. The addition of GCC furthermore provides a source of Ca2+ for plant

Unlike established coating formulations, functional particulate coatings often demand the omission of polymer dispersant so as to retain surface functionality. This results in heterogeneous complex rheology. We take an example from a novel development for an NOx mitigation surface flow filter system, in which ground calcium carbonate (GCC), applied in a coating, reacts with NO2 releasing CO2. Inclusion of mesoporous ancillary mineral acts to capture the CO2. The coating is applied as droplets to maximize gas-contact dynamic by forming a pixelated 2D array using a coating device consisting of protruding pins, which are loaded by submersion in the aqueous coating color such that the adhering droplets are transferred onto the substrate. The flow is driven by surface meniscus wetting causing lateral spread and bulk pore permeation. Filamentation occurs during the retraction of the pins. Stress-related viscoelastic and induced dilatancy in the suspension containing the ancillary mesoporous mineral disrupts processability. Adopting shear, oscillation and extensional rheometric methods, we show that the inclusion of an ancillary mineral that alone absorbs water, e.g., perlite (a naturally occurring porous volcanic glass), is rheologically preferable to one that in addition to absorbing water also immobilizes it on the mineral surface, e.g., sepiolite. When including micro-nanofibrillated cellulose (MNFC), critical for maintaining moisture to support NO2 sorption, it is observed that it acts also as a flow modifier, enabling uniform coating transfer to be achieved, thus eliminating any possible detrimental effect on mineral surface activity by avoiding the use of soluble polymeric dispersant.