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This study aims to develop a new refreshing feeling, ecological, and antimicrobial fabrics for medicinal applications. The geranium essential oils (GEO) are incorporated into polyester and cotton fabrics by different methods, such as ultrasound, diffusion, and padding. The effect of solvent, nature of fibers, and treatment processes were evaluated via the thermal properties, the color strength, the odor intensity, the wash fastness, and the antibacterial activities of the fabrics. It was found that the ultrasound method was the most efficient process for incorporation of GEO. Ultrasound produced a great effect on the color strength of the treated fabrics, suggesting the absorption of geranium oil in fiber surface. The color strength (K/S) increased from 0.22 for the original fabric to 0.91 for the modified counterpart. In addition, the treated fibers showed appreciable antibacterial capacity against Gram-positive (Staphylococcus epidermidis) and Gram-negative (Escherichia coli) bacteria strains. Moreover, the ultrasound process can effectively guarantee the stability of geranium oil in fabrics without decreasing the significant odor intensity and antibacterial character. Based on the interesting properties like ecofriendliness, reusability, antibacterial, and a refreshing feeling, it was suggested that textile impregnated with geranium essential oil might be used as a potential material in cosmetic applications.

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Textile scaffolds that are either 2D or 3D with tunable shapes and pore sizes can be made through textile processing (weaving, knitting, braiding, nonwovens) using microfilaments. However, these filaments lack nano-topographical features to improve bone cell adhesion and proliferation. Moreover, the diameter of such filaments should be higher than that used for classical textiles (10−30 µm) to enable adhesion and the efficient spreading of the osteoblast cell (>30 µm diameter). We report, for the first time, the fabrication of biodegradable nanostructured cylindrical PLLA (poly-L-Lactic acid) microfilaments of diameters 100 µm and 230 µm, using a single step melt-spinning process for straightforward integration of nano-scale ridge-like structures oriented in the fiber length direction. Appropriate drawing speed and temperature used during the filament spinning allowed for the creation of instabilities giving rise to nanofibrillar ridges, as observed by AFM (Atomic Force Microscopy). These micro-filaments were hydrophobic, and had reduced crystallinity and mechanical strength, but could still be processed into 2D/3D textile scaffolds of various shapes. Biological tests carried out on the woven scaffolds made from these nano-structured micro filaments showed excellent human bone cell MG 63 adhesion and proliferation, better than on smooth 30 µm- diameter fibers. Elongated filopodia of the osteoblast, intimately anchored to the nano-structured filaments, was observed. The filaments also induced in vitro osteogenic expression, as shown by the expression of osteocalcin and bone sialoprotein after 21 days of culture. This work deals with the fabrication of a new generation of nano-structured micro-filament for use as scaffolds of different shapes suited for bone cell engineering.

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The immobilization of biocatalysts or other bioactive components often means their transformation from a soluble to an insoluble state by attaching them to a solid support material. Various types of fibrous textiles from both natural and synthetic sources have been studied as suitable support material for biocatalysts immobilization. Strength, inexpensiveness, high surface area, high porosity, pore size, availability in various forms, and simple preparation/functionalization techniques have made textiles a primary choice for various applications. This led to the concept of a new domain called-biocatalysts immobilization on textiles. By addressing the growing advancement in biocatalysts immobilization on textile, this study provides the first detailed overview on this topic based on the terms of preparation, progress, and application in wastewater treatment. The fundamental reason behind the necessity of biocatalysts immobilized textile as well as the potential preparation methods has been identified and discussed. The overall progress and performances of biocatalysts immobilized textile have been scrutinized and summarized based on the form of textile, catalytic activity, and various influencing factors. This review also highlighted the potential challenges and future considerations that can enhance the pervasive use of such immobilized biocatalysts in various sustainable and green chemistry applications.

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Flavin mononucleotide (FMN) derived from Vitamin B2, a bio-based fluorescent water-soluble molecule with visible yellow-green fluorescence, has been used in the scope of producing photoluminescent and glow-in-the-dark patterned polyester (PET) nonwoven panels. Since the FMN molecule cannot diffuse inside the PET fiber, screen printing, coating, and padding methods were used in an attempt to immobilize FMN molecules at the PET fiber surface of a nonwoven, using various biopolymers such as gelatin and sodium alginate as well as a water-based commercial polyacrylate. In parallel, air atmospheric plasma activation of PET nonwoven was carried for improved spreading and adhesion of FMN bearing biopolymer/polymer mixture. Effectively, the plasma treatment yielded a more hydrophilic PET nonwoven, reduction in wettability, and surface roughness of the plasma treated fiber with reduced water contact angle and increased capillary uptake were observed. The standard techniques of morphological properties were explored by a scanning electron microscope (SEM) and atomic force microscopy (AFM). Films combining each biopolymer and FMN were formed on PS (polystyrene) Petri-dishes. However, only the gelatin and polyacrylate allowed the yellow-green fluorescence of FMN molecule to be maintained on the film and PET fabric (seen under ultraviolet (UV) light). No yellow-green fluorescence of FMN was observed with sodium alginate. Thus, when the plasma-activated PET was coated with the gelatin mixture or polyacrylate bearing FMN, the intense photoluminescent yellow-green glowing polyester nonwoven panel was obtained in the presence of UV light (370 nm). Screen printing of FMN using a gelatin mixture was possible. The biopolymer exhibited appropriate viscosity and rheological behavior, thus creating a glow-in-the-dark pattern on the polyester nonwoven, with the possibility of one expression in daylight and another in darkness (in presence of UV light). A bio-based natural product such as FMN is potentially an interesting photoluminescent molecule with which textile surface pattern designers may create light-emitting textiles and interesting aesthetic expressions.

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A graphene/Fe loaded polyester fabric (PET) with robust electrical and catalytic properties has been successfully developed for the first time via a simple coating-incorporation method using hyperbranched poly(amidoamine) (PAMAM) dendrimer as the binder. Both graphene oxide (GO/rGO) and zerovalent iron (Fe0) nanoparticles were loaded on the polyester fabric surface before and after chemical grafting of PAMAM. Full characterization of fabrics before and after modifications has been performed by sessile droplet goniometry, ζ-potential, K/S coating evenness, SEM, XPS, FTIR, TGA and DSC analyses. The results showed successful and uniform coating of GO/rGO and loading of Fe0 on PET and also showed the correlation between the type of chemical moiety responsible for uniform GO coating, high Fe0 loading and their electrical and catalytic activities. Sheet resistance (Rsh) analysis was carried out to measure the conductivity of the samples. The lowest Rsh (corresponding to high conductivity) was found in PET-PAM-rGO-Fe0 (0.74 ± 0.13 kΩ sq-1) followed by PET-rGO-Fe0 (1.32 ± 0.18 kΩ sq-1), PET-PAM-rGO (2.96 ± 0.08 kΩ sq-1) and PET-rGO (3.41 ± 0.34 kΩ sq-1). Furthermore, Fe0-loaded samples were found to be effective in the catalytic removal of toxic water pollutants (crystal violet dye) with ∼99% removal of pollutants in around one hour, as observed by UV-vis spectroscopy. The relatively high electrical conductivity and catalytic activity of PET-PAM-rGO-Fe0 are related to the role played by PAMAM in the uniform rGO coating and high Fe0 loading. These findings are of great importance as they allow envisaging the development of multifunctional textiles for combined smart and green chemistry application.

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This work focuses on the optimization of heterogeneous Fenton-like removal of organic pollutant (dye) from water using newly developed fibrous catalysts based on a full factorial experimental design. This study aims to approximate the feasibility of heterogeneous Fenton-like removal process and optionally make predictions from this approximation in a form of statistical modeling. The fibrous catalysts were prepared by dispersing zerovalent iron nanoparticles on polyester fabrics (PET) before and after incorporation of either polyamidoamine (PAMAM, -NH2) dendrimer, 3-(aminopropyl) triethoxysilane (APTES, -Si-NH2) or thioglycerol (SH). The individual effect of two main factors [pH (X1) and concentration of hydrogen peroxide-[H2O2]µl (X2)] and their interactional effects on the removal process was determined at 95% confidence level by an L27 design. The results indicated that increasing the pH over 5 decreases the dye removal efficiency whereas the rise in [H2O2]µl until equilibrium point increases it. The principal effect of the type of catalysts (PET-NH2-Fe, PET-Si-NH2-Fe, and PET-SH-Fe) did not show any statistical significance. The factorial experiments demonstrated the existence of a significant synergistic interaction effect between the pH and [H2O2]µl as expressed by the values of the coefficient of interactions and analysis of variance (ANOVA). Finally, the functionalization of the resultant fibrous catalysts was validated by electrokinetic and X-ray photoelectron spectroscopy analysis. The optimization made from this study are of great importance for rational design and scaling up of fibrous catalyst for green chemistry and environmental applications.

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The Coronavirus Disease-2019 (COVID-19) pandemic caused by the virus SARS-CoV-2 is spreading very quickly around the world. In less than 7 months since it became known to the international community, the virus has infected 18 million in more than 180 countries and killing more than 700,000 people. Person-to-person transmission through infected respiratory droplets from patients with symptoms and asymptomatic carriers is the main mode of spread in the community. There is currently no standard agreed upon drug to treat the disease and the prospect of having a safe and efficacious vaccine might be years away. Thus, public health interventions such as social distancing and hand washing have been introduced and has, to some extent, slowed the progression of the pandemic. Universal masking as a public health intervention is currently mandatory in a vast majority of countries around the world. To avoid personal protective equipment (PPE) shortage crisis for medical staff and other frontline workers, health authorities are recommending the use cloth masks. Although in theory, cloth masks can be helpful to limit the spread of the COVID-19, serious consideration should be given to the choice of textile, the number of layers of cloth used, pre-treatment of the material with water repellent material and other compounds that can enhance the filtration efficiency of the masks without compromising their breathability. This review uses concepts of textile engineering and the theoretical principles of filtration to make suggestions and recommendations to improve the quality and safety of cloth masks for the general public.

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Flavin mononucleotide (biobased flavin), widely known as FMN, possesses intrinsic fluorescence characteristics. This study presents a sustainable approach for fabricating color-changing intensified light-emitting textiles using the natural compound FMN via digital printing technologies such as inkjet and chromojet. The FMN based ink formulation was prepared at 5 different concentrations using water and glycerol-based systems and printed on cotton duck white (CD), mercerized cotton (MC), and polyester (PET) textile woven samples. After characterizing the printing inks (viscosity and surface tension), the photophysical and physicochemical properties of the printed textiles were investigated using FTIR, UV/visible spectrophotometry, and fluorimetry. Furthermore, photodegradation properties were studied after irradiation under UV (370 nm) and visible (white) light. Two prominent absorption peaks were observed at around 370 nm and 450 nm on K/S spectral curves because of the functionalization of FMN on the textiles via digital printing along with the highest fluorescence intensities obtained for cotton textiles. Before light irradiation, the printed textiles exhibited greenish-yellow fluorescence at 535 nm for excitation at 370 nm. The fluorescence intensity varied as a function of the FMN concentration and the solvent system (water/glycerol). With 0.8 and 1% of FMN, the fluorescence of the printed textiles persisted even after prolonged light irradiation; however, the fluorescence color shifted from greenish-yellow color to turquoise blue then to white, with the fluorescence quantum efficiency values (φ) increasing from 0.1 to a value as high as 1. Photodegradation products of the FMN with varying fluorescence wavelengths and intensities would explain the results. Thus, a color-changing light-emitting fluorescent textile was obtained after prolonged light irradiation of textile samples printed using biobased flavin. Furthermore, multifunctional properties such as antibacterial properties against E. coli were observed only for the printed cotton textile while increased ultraviolet protection was observed for both cotton and polyester printed fabrics for the high concentration of FMN water-based and glycerol-based formulations. The evaluation of fluorescence properties using digital printing techniques aimed to provide more sustainable solutions, both in terms of minimum use of biobased dye and obtaining the maximum yield.

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Bioluminescent living organisms emit light through a specific biocatalyzed reaction involving a luciferin substrate and a luciferase enzyme. The present work investigated the possibility of creating optimal luminescence by immobilization of one or both the enzymes Luciferase (Luc) and FMN reductase (Red) involved in a bioluminescent bacterial system onto a plasma-activated microfibrous PET nonwoven. Parameters affecting the catalytic activity and efficiency of the bacterial system in aqueous medium were determined by luminescence intensity measurements using a luminometer. Two types of plasma, air atmospheric plasma (ATMP) and cold remote plasma (CRPNO) treatment, were used to activate the PET nonwoven. Further, one or both enzyme(s) were immobilized using a physical adsorption technique, without or with the use of natural biopolymers (gelatin and starch) and bovine serum albumin-BSA protein, to improve enzyme stability and activity. Coimmobilization of both Red and Luc enzymes on the CRPNO plasma-activated nonwoven in the presence of BSA led to the maximum luminescence. As high as 60,000 RLU equivalent to that of an LED light used for calibration was observed and showed stable intensity up to 6 min. Fiber surface analysis was tested using wettability tests (water contact angle and capillary uptake), while scanning electron microscopy, atomic force microscopy, and electron spectroscopy for chemical analysis showed changes in fiber surface morphology and chemical functional groups. A considerable increase in "N" atom content after coimmobilization of enzymes in the presence of BSA was detected. This study is the first successful attempt to use a biomimetic strategy for immobilization of enzymes involved in bacterial luminescence on a plasma-activated microfibrous nonwoven in an attempt to attain bioluminescent materials.

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In this study, a flexible multifunctional fibrous membrane for heterogeneous Fenton-like removal of organic and pathogenic contaminants from wastewater was developed by immobilizing zerovalent iron nanoparticles (Fe-NPs) on an amine/thiol grafted polyester membrane. Full characterization of the resulting polyester membranes allowed validation of successful grafting of amine/thiol (NH2 or SH) functional groups and immobilization of Fe-NPs (50-150 nm). The Fenton-like functionality of iron immobilized fibrous membranes (PET-Fe, PET-Si-NH2-Fe, PET-NH2-Fe, and PET-SH-Fe) in the presence of hydrogen peroxide (H2O2) was comparatively studied in the removal of crystal violet dye (50 mg L-1). The effect of pH, amount of iron and H2O2 concentration on dye removal was systematically investigated. The highest dye removal yield reached 98.87% in 22 min at a rate constant 0.1919 min-1 (R 2 = 95.36) for PET-SH-Fe providing 78% toxicity reduction assessed by COD analysis. These membranes could be reused for up to seven repeated cycles. Kinetics and postulated mechanism of colour removal were proposed by examining the above results. In addition, the resultant membranes showed substantial antibacterial activity against pathogenic bacteria (Staphylococcus epidermidis, Escherichia coli) strains studied through disc diffusion-zone inhibitory and optical density analysis. These findings are of great importance because they provide a prospect of textile-based flexible catalysts in heterogeneous Fenton-like systems for environmental and green chemistry applications.

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Robust immobilization of glucose oxidase (GOx) enzyme was achieved on poly(ethylene terephthalate) nonwoven fabric (PN) after integration of favourable surface functional groups through plasma treatments [atmospheric pressure-AP or cold remote plasma-CRP (N2 + O2)] and/or chemical grafting of hyperbranched dendrimers [poly-(ethylene glycol)-OH or poly-(amidoamine)]. Absorption, stability, catalytic behavior of immobilized enzymes and reusability of resultant fibrous bio-catalysts were comparatively studied. Full characterization of PN before and after respective modifications was carried out by various analytical, instrumental and arithmetic techniques. Results showed that modified polyester having amine terminal functional groups pledged better surface property providing up to 31% enzyme loading, and 81% active immobilized enzymes. The activity of the enzyme was measured in terms of interaction aptitude of GOx in a given time to produce hydrogen peroxide using colorimetric assay. The immobilized GOx retained 50% of its original activity after being reused six (06) times and exhibited improved stability compared with the free enzyme in relation to temperature. The reaction kinetics, loading efficiency, leaching, and reusability analysis of enzyme allowed drawing a parallel to the type of organic moiety integrated during GOx immobilization. In addition, resultant fibrous bio-catalysts showed substantial antibacterial activity against pathogenic bacteria strains (Staphylococcus epidermidis and Escherichia coli) in the presence of oxygen and glucose. These results are of great importance because they provide proof-of-concept for robust immobilization of enzymes on surface-modified fibrous polyester fabric for potential bio-industrial applications.

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Flavins are ubiquitous in nature and participate in various biochemical reactions mainly in the form of coenzyme Flavin mononucleotide (FMN) or as precursor such as Riboflavin (RF). Both flavins, RF and FMN are multifunctional bio-based molecules yielding yellow coloration and exhibit photoluminescence, UV protection, and redox properties. The aim of the present research study was to investigate the diffusion method as a technique to obtain photoluminescent cellulosic fabric using multifunctional RF and FMN. The photoluminescent moiety RF and FMN exhibited three maximum absorbance peaks at about 270 nm, 370 nm and 446 nm in aqueous solution at pH 7. The solutions of RF and FMN with concentration 4% and 20% (owf) at pH 7 were prepared and used in diffusion method for cellulosic fabric dyeing. The study involved the determination of color performance and evaluation of luminescence property of the dyed fabric using UV-visible spectrophotometer and photoluminescence spectroscopy, respectively. Under monochromatic UV lamp exposure emitting at 370 nm, the dyed fabric showed an intense emission of greenish yellow color, which was later confirmed by the intense photoluminescence observed at a wavelength of about 570 nm. The study demonstrates the theoretical evaluation of quantum efficiency (φ) obtaining maximum φ value of 0.28. Higher color strength value and improved wash fastness were obtained by treatment with different biobased mordants such as tannic acid and citric acid as well as calcium chloride for both RF and FMN. Additionally, ultraviolet (UV) protection ability for both RF and FMN dyed fabric were determined and showed UPF factor of 50+ and 35 respectively. The work allowed us to explore the photoluminescence property of riboflavin and Flavin mononucleotide for its application in the field of textiles as a new scope of producing photoluminescent textile along with multifunctional properties such as coloration and UV protection.

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Dispersion of iron nanoparticles (Fe-NPs) was achieved on polyester fabrics (PET) before and after the incorporation of dendrimers (PAMAM), 3-(aminopropyl) triethoxysilane (APTES) or thioglycerol (SH). The catalytic activity of the resulting materials (PET-Fe, PET-PAMAM-Fe, PET-APTES-Fe and PET-SH-FE) was comparatively investigated in the degradation of 4-nitrophenol (4-NP) and methylene-blue (MB). Full characterization through diverse instrumental methods allowed correlating the type of the organic moiety incorporated with the Fe content, catalytic properties and stability. The highest 4-NP degradation yield reached 99.6% in 12 min for PET-SH-Fe. The catalytic activity was explained in terms of reactant interaction with Fe-NPs. The 1st order reaction kinetics and pseudo-1st order adsorption kinetics provide evidence of the key role of reactant adsorption. These findings allow envisaging the preparation of fiber-based catalysts for potential uses in environmental and green chemistry.