Optimized Incorporation of Silver Nanoparticles onto Cotton Fabric Using k-Carrageenan Coatings for Enhanced Antimicrobial Properties.

The incorporation of bactericidal properties into textiles is a widely sought-after aspect, and silver nanoparticles (AgNPs) can be used for this. Here, we evaluate a strategy for incorporating AgNPs into a cotton fabric. For this purpose, a bactericidal textile coating based on a composite of AgNPs and kappa-carrageenan (k-CA) was proposed. The composite was obtained by heating the silver precursor (AgNO3) directly in k-CA solution for green synthesis and in situ AgNPs stabilization. Cotton substrates were added to the heated composite solution for surface impregnation and hydrogel film formation after cooling. Direct synthesis of AgNPs on a fabric was also tested. The results showed that the application of a coating based on k-CA/AgNPs composite can achieve more than twice the silver loading on the fabric surface compared to the textile subjected to direct AgNPs incorporation. Furthermore, silver release tests in water showed that higher Ag+ levels were reached for k-CA/AgNPs-coated cotton. Therefore, inoculation tests with the bacteria Staphylococcus aureus (SA) using the agar diffusion method showed that samples covered with the composite resulted in significantly larger inhibition halos. This indicated that the use of the composite as a coating for cotton fabric improved its bactericidal activity against SA.

Carbon fiber felt scaffold from Brazilian textile PAN fiber for regeneration of critical size bone defects in rats: A histomorphometric and microCT study.

The objective of the present study was to evaluate the carbon fiber obtained from textile PAN fiber, in its different forms, as a potential scaffolds synthetic bone. Thirty-four adult rats were used (Rattus norvegicus, albinus variation), two critical sized bone defects were made that were 5 mm in diameter. Twenty-four animals were randomly divided into four groups: control (C)-bone defect + blood clot, non-activated carbon fiber felt (NACFF)-bone defect + NACFF, activated carbon fiber felt (ACFF)-bone defect + ACFF, and silver activated carbon fiber felt (Ag-ACFF)-bone defect + Ag-ACFF, and was observed by 15 and 60 days for histomorphometric, three-dimensional computerized microtomography (microCT) and mineral apposition analysis. On histomorphometric and microCT analyses, NACFF were associated with higher proportion of neoformed bone and maintenance of bone structure. On fluorochrome bone label, there was no differences between the groups. NACFF has shown to be a promising synthetic material as a scaffold for bone regeneration.

Emerging pollutants in textile wastewater: an ecotoxicological assessment focusing on surfactants.

Water and several chemicals, including dyestuffs, surfactants, acids, and salts, are required during textile dyeing processes. Surfactants are harmful to the aquatic environment and induce several negative biological effects in exposed biota. In this context, the present study aimed to assess acute effects of five surfactants, comprising anionic and nonionic classes, and other auxiliary products used in fiber dyeing processes to aquatic organisms Vibrio fischeri (bacteria) and Daphnia similis (cladocerans). The toxicities of binary surfactant mixtures containing the anionic surfactant dodecylbenzene sulfonate + nonionic fatty alcohol ethoxylate and dodecylbenzene sulfonate + nonionic alkylene oxide were also evaluated. Nonionic surfactants were more toxic than anionic compounds for both organisms. Acute nonionic toxicity ranged from 1.3 mg/L (fatty alcohol ethoxylate surfactant) to 2.6 mg/L (ethoxylate surfactant) for V. fischeri and from 1.9 mg/L (alkylene oxide surfactant) to 12.5 mg/L (alkyl aryl ethoxylated and aromatic sulfonate surfactant) for D. similis, while the anionic dodecylbenzene sulfonate EC50s were determined as 66.2 mg/L and 19.7 mg/L, respectively. Both mixtures were very toxic for the exposed organisms: the EC50 average in the anionic + fatty alcohol ethoxylate mixture was of 1.0 mg/L ± 0.11 for V. fischeri and 4.09 mg/L ± 0.69 for D. similis. While the anionic + alkylene oxide mixture, EC50 of 3.34 mg/L for D. similis and 3.60 mg/L for V. fischeri. These toxicity data suggested that the concentration addition was the best model to explain the action that is more likely to occur for mixture for the dodecylbenzene sulfonate and alkylene oxide mixtures in both organisms. Our findings also suggest that textile wastewater surfactants may interact and produce different responses in aquatic organisms, such as synergism and antagonism. Ecotoxicological assays provide relevant information concerning hazardous pollutants, which may then be adequately treated and suitably managed to reduce toxic loads, associated to suitable management plans.

Application of Thermomyces lanuginosus polygalacturonase produced in Komagataella phaffii in biomass hydrolysis and textile bioscouring.

In this work, the polygalacturonase (TL-PG1) from the thermophilic fungus Thermomyces lanuginosus was heterologously produced for the first time in the yeast Komagataella phaffii. The TL-PG1 was successfully expressed under the control of the AOX1 promoter and sequentially purified by His-tag affinity. The purified recombinant pectinase exhibited an activity of 462.6 U/mL toward polygalacturonic acid under optimal conditions (pH 6 and 55 ˚C) with a 2.83 mg/mL and 0.063 µmol/minute for Km and Vmax, respectively. When used as supplementation for biomass hydrolysis, TL-PG1 demonstrated synergy with the enzymatic cocktail Ctec3 to depolymerize orange citrus pulp, releasing 1.43 mg/mL of reducing sugar. In addition, TL-PG1 exhibited efficiency in fabric bioscouring, showing potential usage in the textile industry. Applying a protein dosage of 7 mg/mL, the time for the fabric to absorb water was 19.77 seconds (ten times faster than the control). Adding the surfactant Triton to the treatment allowed the reduction of the enzyme dosage by 50% and the water absorption time to 6.38 seconds. Altogether, this work describes a new versatile polygalacturonase from T. lanuginosus with the potential to be employed in the hydrolysis of lignocellulosic biomass and bioscouring.

Efficient bioremediation of indigo-dye contaminated textile wastewater using native microorganisms and combined bioaugmentation-biostimulation techniques.

In this work, the bioremediation of wastewater from the textile industry with indigo dye content was carried out using combined bioaugmentation, bioventilation, and biostimulation techniques. Initially, the inoculum was prepared by isolating the microorganisms from the textile wastewater in a 2 L bioreactor. Then, the respirometry technique was implemented to determine the affinity of the microorganisms and the substrate by measuring CO2 and allowed the formulation of an empirical mathematical model for the growth kinetics of the microorganism. Finally, the bioremediation was carried out in a 3 L bioreactor obtaining an indigo dye removal efficiency of 20.7 ± 1.2%, 24.0 ± 1.5%, and 29.7 ± 1.1% for equivalent wavelengths of 436 nm, 525 nm, and 620 nm. The chemical oxygen demand showed an average reduction of 88.9 ± 2.5%, going from 470.7 ± 15.6 to 52.3 ± 10.7 ppm after 30 days under constant agitation and aeration. A negative generalized exponential model was fitted to assess the affinity of the microorganism with the wastewater as a substrate by evaluating the production of CO2 during the bioremediation. Bioremediation techniques improve water discharge parameters compared to chemical treatments implemented in the industry, reducing the use of substances that can generate secondary pollution. Bioaugmentation, biostimulation, and bioventing of the textile wastewater in this study demonstrate the potential of these combined techniques to serve as an efficient alternative for indigo-contaminated wastewater in the textile industry.

Antimicrobial finishing of textiles using nanomaterials / Acabamento antimicrobiano de têxteis a partir da utilização de nanomateriais

Metals, such as copper and silver, can be extremely toxic to bacteria at exceptionally low concentrations. Because of this biocidal activity, metals have been widely used as antimicrobial agents in a multitude of applications related with agriculture, healthcare, and the industry in general. A large number of microorganisms live in the human environment. if the balance of these creatures in nature is disturbed, the health of the individual and society will be threatened due to the production and emission of unpleasant odors and the reduction of health standards. The presence of microorganisms on textiles can cause adverse effects such as discoloration or staining on textiles, decomposition of fibrous materials, reduced strength, and eventually decay of textiles. Most fibers and polymers do not show resistance to the effects of microbes and by providing growth factors for microorganisms such as the right temperature and humidity, nutrients from sweat and fat from skin glands, dead skin cells as well as materials used in the stage of finishing the textiles causes the rapid growth and spread of various microbes. With the advent of nanotechnology, various industries and human daily life underwent changes. In recent years, increasing research on nanoparticles has led to the production of textiles with greater efficiency and added value. These modified textiles prevent the spread of unpleasant odors, the spread, and transmission of diseases. This article reviews the basics and principles of antimicrobial tetiles, as well as a brief overview of antimicrobial materials and nanostructures with antimicrobial properties.

Metais como cobre e prata podem ser extremamente tóxicos para bactérias em concentrações excepcionalmente baixas. Devido a esta atividade biocida, os metais têm sido amplamente utilizados como agentes antimicrobianos em uma infinidade de aplicações relacionadas à agricultura, saúde e indústria em geral. Muitos microrganismos vivem no ambiente humano e, se o equilíbrio dessas criaturas na natureza for alterado, a saúde dos indivíduos e da sociedade estará ameaçada devido à produção e emissão de odores desagradáveis e à redução dos padrões de saúde. A presença de microrganismos em têxteis pode causar efeitos adversos, como descoloração ou manchas, decomposição de materiais fibrosos, resistência reduzida e, eventualmente, deterioração. A maioria das fibras e polímeros não apresenta resistência aos efeitos dos micróbios e fornecem fatores de crescimento para os microrganismos, como temperatura e umidade adequadas, nutrientes do suor e gordura das glândulas da pele, células mortas da pele, bem como materiais usados na etapa de acabamento causando crescimento e disseminação de vários micróbios. Com o advento da nanotecnologia, diversas indústrias e o cotidiano humano passaram por mudanças. Nos últimos anos, o aumento da pesquisa em nanopartículas levou à produção de têxteis com maior eficiência e valor agregado. Esses têxteis modificados evitam a propagação de odores desagradáveis, a propagação e a transmissão de doenças. Este artigo analisa os fundamentos e princípios dos têxteis antimicrobianos, bem como uma breve visão geral dos materiais antimicrobianos e nanoestruturas com propriedades antimicrobianas.

Reutilización de barrera de tela de algodón estéril en la práctica clínica: estudio observacional longitudinal / Reusing sterile cotton fabric barriers in the clinical practice: an observational and longitudinal study / Reuso de barreira estéril de tecido de algodão na prática clínica: estudo longitudinal observacional

Objetivo: analizar las características de barrera física y biológica de los campos de algodón utilizados como sistema de barrera estéril después de ser sometidos a múltiples usos y procesos en la práctica clínica. Método: estudio observacional longitudinal de seguimiento y evaluación de tela 100% algodón, utilizada como sistema de barrera estéril en un hospital de mediano porte. Se recolectaron muestras antes del uso (después de tres lavados) y después de tres, seis, nueve, 12 y 15 meses de uso y se evaluaron el número, grosor e integridad de los hilos, peso, absorción de agua y penetración húmeda de microorganismos. Resultados: después de 85 lavados, no cambió el número de hilos, aumentó el número de fibras deshilachadas y el volumen de agua absorbida. La prueba microbiológica mediante la metodología estándar alemana obtuvo un resultado negativo y la de penetración húmeda de microorganismos no mostró cambios significativos con el tiempo, a pesar de que una fracción de células microbianas pasó a través de las muestras de doble capa. Conclusión: las propiedades físicas de la tela 100% algodón utilizada como sistema de barrera estéril cambiaron con el uso/procesamiento; sin embargo, no interfirieron significativamente con los resultados obtenidos en las pruebas realizadas a la barrera microbiológica hasta los 85 lavados.

Objective: to analyze the physical and biological barrier characteristics of cotton fields used as a sterile barrier system after multiple use and processing cycles in the clinical practice. Method: an observational and longitudinal study to monitor and evaluate 100% cotton fabric used as a sterile barrier system in a medium-sized hospital. Samples were collected before use (after three washes) and at three, six, nine, 12 and 15 months of use and evaluated for the number, thickness and integrity of threads, weight, water absorption and wet penetration by microorganisms. Results: after 85 washes, the number of threads remained unchanged, and the shredded fibers and the water volume absorbed were increased. The microbiological test using the German standard methodology obtained a negative result and wet penetration by microorganisms did not show significant changes over time, although a percentage of the microbial cells passed through the double-layer samples. Conclusion: the physical properties of 100% cotton used as a sterile barrier system changed with use/processing cycles; however, these alterations did not significantly interfere with the results obtained by the tests performed on the microbiological barrier up to 85 washes.

Objetivo: analisar as características de barreira física e biológica de campos de algodão, que são utilizados como sistema de barreira estéril, após múltiplos usos e processamentos na prática clínica. Método: estudo longitudinal observacional de acompanhamento e de avaliação de tecido 100% algodão que foi utilizado como sistema de barreira estéril em um hospital de médio porte. Amostras foram coletadas antes do uso (após três lavagens) e com três, seis, nove, 12 e 15 meses de uso e avaliadas quanto ao número, à espessura e à integridade dos fios, peso, absorção de água e penetração úmida de micro-organismos. Resultados: após 85 lavagens, o número de fios permaneceu inalterado, porém aumentaram-se as fibras desfiadas e o volume de água absorvido. O teste microbiológico utilizando metodologia padrão alemão obteve resultado negativo; já o de penetração de úmida de micro-organismos não apresentou mudanças significativas ao longo do tempo, embora uma fração das células microbianas tenham passado pelas amostras de dupla camada. Conclusão: as propriedades físicas do tecido 100% algodão, utilizado como sistema de barreira estéril, alteraram com usos/processamentos; entretanto essas não interferiram significativamente nos resultados obtidos pelos testes realizados na barreira microbiológica até 85 lavagens.

Silk wastes and autoclaved degumming as an alternative for a sustainable silk process.

Silk degumming is considered the first point in the preparation of silk-based materials since this process could modify the silk fiber and the properties of its related products. This study evaluated the differences in morphology, secondary structure, amino acid content, thermal stability, and mechanical properties of two types of raw materials, defective cocoons (DC) and silk fibrous waste (SW), degummed by chemical (C) and autoclaving (A) methods. Subsequently, silk fibroin films were prepared by dissolving each type of degummed fibers, and thermal and structural films properties were determined. The findings demonstrated that autoclaving is an efficient alternative to remove silk sericin, as the resulting fibers presented improved structural, thermal, and mechanical properties compared to those obtained by the chemical method. For films preparation, autoclave resulted in a good option, but dissolution parameters need to be adjusted for defective cocoons. Furthermore, similarities between the physicochemical properties of fibers and films from both fibrous wastes suggest that SW is a promising raw material for producing fibrous resources and regenerated silk fibroin materials. Overall, these findings suggest new recycling methods for fibrous waste and by-products generated in the silk textile production process.

Ecotoxicological response surface analysis of salt and pH in textile effluent on Bacillus subtilis and Lactuca sativa.

Textile effluents, although their composition can vary considerably, typically contain high levels of dissolved salts and exhibit wide variations in pH. Ecotoxicological studies regarding the effects of these parameters, however, have been limited owing to the need for sensitive and easy-to-handle bioindicators that require low amounts of sampling, are cost-effective, time-efficient, and ethically endorsed. This kind of study, additionally, demands robust multi-factorial statistical designs that can accurately characterize the individual and combined relationship between variables. In this research, Response Surface Methodology (RSM) was used to calculate the individual and interaction effects of NaCl concentration and pH value of a Simulated Textile Effluent (STE) on the development rate (DR) of the bioindicators: Bacillus subtilis bacteria and Lactuca sativa lettuce. The results demonstrated that the bioindicators were sensitive to both NaCl and pH factors, where the relative sensitivity relationship was B. subtilis > L. sativa. The quadratic equations generated in the experiments indicated that increased concentrations of 50-250 mg L-1 of NaCl caused a perturbance of 1.40%-34.40% on the DR of B. subtilis and 0.50%-12.30% on L. sativa. The pH factor at values of 3-11 caused an alteration of 27.00%-64.78% on the DR of the B. subtilis and 51.37%-37.37% on the L. sativa. These findings suggest that the selected bioindicators could serve as effective tools to assess the ecotoxicological effects of textile effluents on different ecological systems, and the RSM was an excellent tool to consider the ecotoxicological effects of the parameters and to describe the behavior of the results. In conclusion, the NaCl and pH factors may be responsible for disrupting different ecosystems, causing imbalances in their biodiversity and biomass. Before discharge or reuse, it is suggested to remove salts and neutralize pH from textile effluents and, mostly, develop novel, eco-friendlier textile processing techniques.

Cellulosic and microplastic fibers in the Antarctic fish Harpagifer antarcticus and Sub-Antarctic Harpagifer bispinis.

Human settlements within the Antarctic continent have caused significant coastal pollution by littering plastic. The present study assessed the potential presence of microplastics in the gastrointestinal tract of the Antarctic fish Harpagifer antarcticus, endemic to the polar region, and in the sub-Antarctic fish Harpagifer bispinis. H. antarcticus. A total of 358 microfibers of multiple colors were found in 89 % of H. antarcticus and 73 % of H. bispinis gastrointestinal track. A Micro-FTIR analysis characterized a sub-group (n = 42) of microfibers. It revealed that most of the fibers were cellulose (69 %). Manmade fibers such as microplastics polyethylene terephtalate, acrylics, and semisynthetic/natural cellulosic fibers were present in the fish samples. All the microfibers extracted were textile fibers of blue, black, red, green, and violet color. Our results suggest that laundry greywater discharges of human settlements near coastal waters in Antarctica are a major source of these pollutants in the Antarctic fish.

Biopolishing of denim by the recombinant xylanase II of Caulobacter crescentus.

Denim, also known as jeans, is a fabric made up of braided cotton threads dyed indigo blue, whose fibers contain approximately 10% of non-cellulosic impurities that reduce its commercial value. Microbial enzymes can act in the cleaning and desizing processes of jeans, improving their color, softness, and covering capacity. The recombinant Xylanase II (XynA2) from the aquatic bacterial Caulobacter crescentus (C. crescentus), previously characterized in terms of its biochemical features, was applied to the biotreatment of jeans to clean and degum it. The biotreatment performance was evaluated in terms of tissue weight loss, amount of reducing sugars released and analysis of the images obtained by scanning electron microscopy (SEM). Biotreated tissues, at 12 and 24 h, showed a dry weight loss of 4.9 and 6.6%, respectively. The reducing sugars amount released after XynA2 action over the jean's fibers showed statistically significant values when compared with each other and with their respective controls. SEM images clearly shown that the fabric treated for 12 h presented a smooth and polished surface, while the fabric treated for 24 h showed the cotton fibers broken, displaying severe damage to the textile. The best treatment for the jeans was in the presence of 1 U mg-1 XynA2 at pH 8 and 60 °C during 12 h. In conclusion, XynA2 of C. crescentus was satisfactorily applied for the biopolishing of denim jeans being a more sustainable alternative to the use of chemical and abrasive processes to obtain the same effects.

Employ a Clay@TMSPDETA hybrid material as an adsorbent to remove textile dyes from wastewater effluents.

A grafting of N1-(3-trimethoxysilylpropyl)diethylenetriamine (TMSPDETA) on natural clay was carried out to obtain an organic-inorganic hybrid clay material that was applied as an adsorbent to the uptake of Reactive Blue 19 (RB-19) and Reactive Green 19 (RG-19) dyes from aqueous wastewaters. This research demonstrates the effect of TMSPDETA contents on amino-functionalized clay materials' hydrophobic/hydrophilic behavior. The resultant material was utilized to uptake reactive dyes in aqueous solutions. The clay@TMSPDETA hybrid material was characterized by isotherm of adsorption and desorption of nitrogen, FTIR, elemental analysis, TGA, pHpzc, total acidity, total basicity groups, and hydrophilic balance. The hybrid samples were more hydrophilic than the pristine clay for ratios from 0.1 up to 0.5 due to adding amino groups to the pristine clay. FTIR spectra suggest that TMSPDETA was grafted onto the clay. The hybrid material presents a surface area 2.17-fold (42.7 m2/g) lower than pristine clay (92.7 m2/g). The total volume of pores of hybrid material was 0.0822 cm3/g, and the pristine clay material was 0.127 cm3/g, corresponding to a diminution of the total pore volume (Vtot) of 1.54 times. The kinetic data followed the pseudo-second-order (PSO) model for RB-19 and RG-19 reactive dyes. The equilibrium data were better fitted to the Liu isotherm model, displaying a Qmax as 178.8 and 361.1 mg g-1 for RB-19 and RG-19, respectively, at 20.0 °C. The main mechanism of interactions of the reactive dyes with the hybrid clay is electrostatic interaction. The clay@TMSPDETA has a very good effect on treating synthetic dye-textile wastewater. The removal percentage of simulated wastewater was up to 97.67% and 88.34% using distilled water and plastic industry wastewater as the solvents, respectively. The clay@TMSPDETA-0.1 could be recycled up to 5 cycles of adsorption and desorption of both dyes, attaining recoveries of 98.42% (RB-19) and 98.32% (RG-19) using 0.1 M HCl + 10% ethanol.

Biogenic production of silver, zinc oxide, and cuprous oxide nanoparticles, and their impregnation into textiles with antiviral activity against SARS-CoV-2.

Nanotechnology is being used to fight off infections caused by viruses, and one of the most outstanding nanotechnological uses is the design of protective barriers made of textiles functionalized with antimicrobial agents, with the challenge of combating the SARS-CoV-2 virus, the causal agent of COVID-19. This research is framed within two fundamental aspects: the first one is linked to the proposal of new methods of biogenic synthesis of silver, cuprous oxide, and zinc oxide nanoparticles using organic extracts as reducing agents. The second one is the application of nanomaterials in the impregnation (functionalization) of textiles based on methods called "in situ" (within the synthesis), and "post-synthesis" (after the synthesis), with subsequent evaluation of their effectiveness in reducing the viral load of SARS-CoV-2. The results show that stable, monodisperse nanoparticles with defined geometry can be obtained. Likewise, the "in situ" impregnation method emerges as the best way to adhere nanoparticles. The results of viral load reduction show that 'in situ' textiles with Cu2O NP achieved a 99.79% load reduction of the SARS-CoV-2 virus.

PLA/modified-starch blends and their application for the fabrication of non-woven fabrics by melt-blowing.

Blends of polylactic acid (PLA) and thermoplastic starch (TS) with and without chemical modification were obtained by melt extrusion and used to obtain non-woven fabrics by melt-blowing for the first time. Different TS were obtained by reactive extrusion from native cassava, oxidized, maleated, and dual modified (oxidized and maleated) starch. The chemical modification of starch decreases the difference in viscosity and favors blending, resulting in more homogeneous morphologies, unlike the blends with unmodified TS, which displayed a visible phase separation with large TS droplets. The dual modified starch showed a synergistic effect to process TS by melt-blowing. Regarding non-woven fabrics, values in diameter (2.5-82.1 µm), thickness (0.4-0.6 mm), and grammage (49.9-103.8 g/m2) were explained due to differences in viscosity of the components, and to the fact that during melt the hot air preferentially stretches and thins the areas without large droplets of TS. Moreover, plasticized starch acts as a flow modifier. The porosity of the fibers increased with the addition of TS. Further studies and optimization of blends with low contents of TS and type starch modification will be necessary to completely understand these systems with very complex behavior to obtain non-woven fabrics with improved properties and application.

Textiles impregnated with antimicrobial substances in healthcare services: systematic review.

Background: Antimicrobial textiles have proved to be a promising biosafety strategy. Thus, the current study was focused on identifying which antimicrobial substances impregnated in textiles used in healthcare services confer efficacy in reducing the microbial load present in these textiles and/or the Healthcare-Associated Infection (HAI) rates, when compared to conventional textiles. Methods: A systematic review of intervention studies using MEDLINE via the PubMed portal, EMBASE, CINAHL, Web of Science, Scopus, Google Scholar and medRxiv. The studies identified were selected according to eligibility criteria and submitted to data extraction and methodological quality evaluation through Joanna Briggs Institute specific tools. The outcomes were synthesized qualitatively. Results: 23 studies were selected to comprise the final sample, in which antimicrobial textiles were used by hospitalized patients, by health professionals during work shifts and in inanimate healthcare environments. Conclusions: Copper, silver, zinc oxide, titanium and silver-doped titanium impregnated in textiles used by patients confer efficacy in reducing the microbial load of these textiles and/or the HAI rates. Quaternary ammonium, chlorhexidine, silver and copper together, quaternary ammonium, alcohols and isothiazolone derivatives together, chitosan and dimethylol dimethyl hydantoin together, all impregnated in textiles used by health professionals confer efficacy in reducing the microbial load of these textiles. Quaternary ammonium impregnated in textiles used in inanimate healthcare environments confers efficacy in reducing the microbial load of these textiles.

Antimicrobial finishing of textiles using nanomaterials.

Metals, such as copper and silver, can be extremely toxic to bacteria at exceptionally low concentrations. Because of this biocidal activity, metals have been widely used as antimicrobial agents in a multitude of applications related with agriculture, healthcare, and the industry in general. A large number of microorganisms live in the human environment. if the balance of these creatures in nature is disturbed, the health of the individual and society will be threatened due to the production and emission of unpleasant odors and the reduction of health standards. The presence of microorganisms on textiles can cause adverse effects such as discoloration or staining on textiles, decomposition of fibrous materials, reduced strength, and eventually decay of textiles. Most fibers and polymers do not show resistance to the effects of microbes and by providing growth factors for microorganisms such as the right temperature and humidity, nutrients from sweat and fat from skin glands, dead skin cells as well as materials used in the stage of finishing the textiles causes the rapid growth and spread of various microbes. With the advent of nanotechnology, various industries and human daily life underwent changes. In recent years, increasing research on nanoparticles has led to the production of textiles with greater efficiency and added value. These modified textiles prevent the spread of unpleasant odors, the spread, and transmission of diseases. This article reviews the basics and principles of antimicrobial tetiles, as well as a brief overview of antimicrobial materials and nanostructures with antimicrobial properties.

Synthetic microfiber emissions from denim industrial washing processes: An overlooked microplastic source within the manufacturing process of blue jeans.

In recent years, domestic laundry has been recognized as a relevant source of microfiber (MF) pollution to aquatic environments. Nevertheless, the MF emissions from industrial washing processes in real world scenarios have not been quantified. The aim of this study was to quantify the MF emissions from 3 industrial washing processes (rinse wash, acid wash and enzymatic wash) commonly employed in the manufacturing process of blue jeans. The blue jeans were characterized by ATR-FT-IR, SEM and TGA to study the morphology, the polymer chemical identity and the proportion of synthetic and natural fibers, respectively. The MF emissions were quantified as the MF mass and number emitted per washed jean. All the industrial washing processes released a majority of synthetic MF. The enzymatic wash produced the highest amount of MF, with 1423 MF per gram of fabric (MF/g) equivalent to 381.7 MF grams per gram of fabric (MF g/g), followed by the acid wash with 253 MF/g equivalent to 142.7 MF g/g and lastly the rinse wash with 133 MF/g equivalent to 62.3 MF g/g. Statistically significant differences between the MF sizes for all washing processes were found when evaluating the emissions by MF/g, however, the previous trend was not found for MF g/g. Moreover, the total MF emissions of an industrial washing process of a pair of blue jeans during its manufacture process are up to 10.95 times higher than the reported domestic washing estimates performed by the consumer available in the published literature. We demonstrate that studying industrial washing procedures of textile garments will improve the accuracy of the current estimates of MF emissions available in published reports, which will ultimately aid in the development of regulations for MF emissions at an industrial level.

Cuprous oxide nanoparticles incorporated into a polymeric matrix embedded in fabrics to prevent spread of SARS-CoV-2.

This paper describes the development of a coating for cotton and polypropylene (PP) fabrics based on a polymeric matrix embedded with cuprous oxide nanoparticles (Cu2O@SDS NPs) in order to inactivate SARS-CoV-2 and manufactured by a simple process using a dip-assisted layer-by-layer technology, at low curing temperature and without the need for expensive equipment, capable of achieving disinfection rates of up to 99%. The polymeric bilayer coating makes the surface of the fabrics hydrophilic, enabling the transportation of the virus-infected droplets to achieve the rapid inactivation of SARS-CoV-2 by contact with the Cu2O@SDS NPs incorporated in the coated fabrics.

Inka Unku: Imperial or provincial? State-local relations.

Standardized Inka tunics, or unku, were created under the auspices of the state as symbolic expressions of its expansionist power. To ensure these textiles acquired the status of effective insignias of power and territorial control, the Inka established and imposed technical and stylistic canons for their production (techne) by means of highly-skilled state weavers. In the provinces, social groups that came under imperial rule, local expert weaving agents adopted the conventions of the state and included meaningful symbolic elements of the idiosyncrasies, traditions, and experiential knowledge of the local community (metis). We therefore propose that this was not a unidirectional process and that the Caleta Vitor Inka unku (hereon referred to as the CV unku), presented here, reflects a syncretism promoted by local weavers. In terms of methods, we have developed a decoding tool for the unku, with the aim of distinguishing state from local hallmarks, thereby revealing the syncretic complexity of these iconic tunics. This methodological tool is based on a series of standard analytical parameters and attributes linked to morphological, technological, and stylistic features, which we applied to the CV unku. Unlike others, this unku does come from a looted tomb but was scientifically excavated in a cemetery located in the Caleta Vitor Bay in northern Chile. By deconstructing the CV unku we determined the steps in the chaîne opératoire at which local technical and stylistic elements were incorporated, thus affecting or transforming, in part, its emblematic imperial imagery. This study also marks a step forward in our understanding of a syncretic landscape that combines the state worldview and organized production system (imperial Inka) with craft-production practices that were rooted in provincial and local communities (provincial Inka).

Análisis microbiológico a corto y largo plazo del material usado para esterilizar instrumental odontológico / Short and long-term microbiological analysis of the material for sterilize dental instruments

Introducción: el material para empaquetar el instrumental odontológico, como pueden ser bolsas de tela, papel o plástico, es usado por profesionales de la salud; sin embargo, es necesario esclarecer la efectividad de cada uno y determinar el tiempo que permanece estéril luego del procedimiento. Objetivo: identificar la eficacia de tela, plástico y papel como materiales para esterilizar instrumental a corto y largo plazo. Material y métodos: se realizaron cultivos sólidos y líquidos de instrumental esterilizado en tres materiales y con diferentes tiempos de postesterilización. Se incubaron a 36 oC por 72 horas en condiciones aerobias y anaerobias. Los resultados se analizaron usando una prueba de Kruskal-Wallis, seguida de una prueba de Dunn. Resultados: los resultados mostraron que inmediatamente después del proceso de esterilización, los tres materiales son efectivos (Kruskal-Wallis test, p = 0.2752), 24 horas (p = 0.2492), siete (p = 0.0509) y 14 días (p = 0.0006). Veinticuatro horas posterior a la esterilización la tela no es efectiva, el plástico disminuye su efectividad y el papel sigue siendo efectivo. Conclusión: en nuestros resultados, el papel es la mejor opción para esterilizar instrumental (AU)

Introduction: material such as cloth, paper or plastic bags to wrap dental instruments is used by health professionals, however, it is necessary to clarify the effectiveness of each one and determine if it remains sterile after the procedure. Objective: to determine the effectiveness of cloth, plastic and paper as materials to sterilize dental instruments in the short and long term. Material and methods: we carry out solid and liquid cultures of sterilized instruments in three materials, at different post-sterilization times, incubated at 36 oC for 72 hours under aerobic and anaerobic conditions, and the results were analyzed using a Kruskal-Wallis test, followed by from a Dunn's test. Results: our results showed that immediately after the sterilization process the three materials are effective (Kruskal-Wallis; p = 0.2752), 24 hours (p = 0.2492), 7 (p = 0.0509) and 14 (p = 0.0006) days. Twenty-four hours after the cloth is not effective, plastic decreases its effectiveness and paper remain effective. Conclusion: in our results, paper is the best option to sterilize dental instruments (AU)