Project description:The COVID-19 pandemic is currently causing a severe disruption and shortage in the global supply chain of necessary personal protective equipment (e.g., N95 respirators). The U.S. CDC has recommended use of household cloth by the general public to make cloth face coverings as a method of source control. We evaluated the filtration properties of natural and synthetic materials using a modified procedure for N95 respirator approval. Common fabrics of cotton, polyester, nylon, and silk had filtration efficiency of 5-25%, polypropylene spunbond had filtration efficiency 6-10%, and paper-based products had filtration efficiency of 10-20%. An advantage of polypropylene spunbond is that it can be simply triboelectrically charged to enhance the filtration efficiency (from 6 to >10%) without any increase in pressure (stable overnight and in humid environments). Using the filtration quality factor, fabric microstructure, and charging ability, we are able to provide an assessment of suggested fabric materials for homemade facial coverings.
Project description:Rationale Microplastics are a pressing global concern and inhalation of microplastic fibers has been associated with interstitial and bronchial inflammation in flock workers. However, how microplastic fibers affect the lungs is unknown. Objectives Our aim was to assess the effects of 12x31 µm nylon 6,6 (nylon) and 15x52 µm polyethylene terephthalate (polyester) textile microplastic fibers on lung epithelial growth and differentiation. Methods We used human and murine alveolar and airway-type organoids as well as air-liquid interface cultures derived from primary lung epithelial progenitor cells and incubated these with either nylon or polyester fibers or nylon leachate. In addition, mice received one dose of nylon fibers or nylon leachate and 7 days later organoid-forming capacity of isolated epithelial cells was investigated. Results We observed that nylon microfibers, more than polyester, inhibited developing airway organoids and not established ones. This effect was mediated by components leaching from nylon. Epithelial cells isolated from mice exposed to nylon fibers or leachate, also formed fewer airway organoids, suggesting long-lasting effects of nylon components on epithelial cells. Part of these effects were recapitulated in human air-liquid interface cultures. Transcriptome analysis revealed upregulation of Hoxa5 post-exposure to nylon fibers. Inhibiting Hoxa5 protein during nylon exposure restored airway organoid formation, confirming Hoxa5's pivotal role in the effects of nylon. Conclusions These results suggest that components leaching from nylon 6,6 may especially harm developing airways and/or airways undergoing repair and we strongly encourage to characterize both hazard of and exposure to microplastic fibers in more detail.
Project description:BACKGROUND:Estimation of glomerular filtration rate (GFR) using estimated glomerular filtration rate creatinine (eGFRcr) is central to clinical practice but has limitations. We tested the hypothesis that serum metabolomic profiling can identify novel markers that in combination can provide more accurate GFR estimates. METHODS:We performed a cross-sectional study of 200 African American Study of Kidney Disease and Hypertension (AASK) and 265 Multi-Ethnic Study of Atherosclerosis (MESA) participants with measured GFR (mGFR). Untargeted gas chromatography/dual mass spectrometry- and liquid chromatography/dual mass spectrometry-based quantification was followed by the development of targeted assays for 15 metabolites. On the log scale, GFR was estimated from single- and multiple-metabolite panels and compared with eGFR using the Chronic Kidney Disease Epidemiology equations with creatinine and/or cystatin C using established metrics, including the proportion of errors >30% of mGFR (1-P30), before and after bias correction. RESULTS:Of untargeted metabolites in the AASK and MESA, 283 of 780 (36%) and 387 of 1447 (27%), respectively, were significantly correlated (P???0.001) with mGFR. A targeted metabolite panel eGFR developed in the AASK and validated in the MESA was more accurate (1-P30 3.7 and 1.9%, respectively) than eGFRcr [11.2 and 18.5%, respectively (P?<?0.001 for both)] and estimating GFR using cystatin C (eGFRcys) [10.6% (P?=?0.02) and 9.1% (P?<?0.05), respectively] but was not consistently better than eGFR using both creatinine and cystatin C [3.7% (P?>?0.05) and 9.1% (P?<?0.05), respectively]. A panel excluding creatinine and demographics still performed well [1-P30 6.4% (P?=?0.11) and 3.4% (P?<?0.001) in the AASK and MESA] versus eGFRcr. CONCLUSIONS:Multimetabolite panels can enable accurate GFR estimation. Metabolomic equations, preferably excluding creatinine and demographic characteristics, should be tested for robustness and generalizability as a potential confirmatory test when eGFRcr is unreliable.
Project description:Toward the objective of developing platform technologies for anti-infective materials based upon photodynamic inactivation, we employed electrospinning to prepare a non-woven textile comprised of polyacrylonitrile nanofibers embedded with a porphyrin-based cationic photosensitizer; termed PAN-Por(+). Photosensitizer loading was determined to be 34.8 nmol/mg material; with thermostability to 300 °C. Antibacterial efficacy was evaluated against four bacteria belonging to the ESKAPE family of pathogens (Staphylococcus aureus; vancomycin-resistant Enterococcus faecium; Acinetobacter baumannii; and Klebsiella pneumonia), as well as Escherichia coli. Our results demonstrated broad photodynamic inactivation of all bacterial strains studied upon illumination (30 min; 65 ± 5 mW/cm²; 400-700 nm) by a minimum of 99.9996+% (5.8 log units) regardless of taxonomic classification. PAN-Por(+) also inactivated human adenovirus-5 (~99.8% reduction in PFU/mL) and vesicular stomatitis virus (>7 log units reduction in PFU/mL). When compared to cellulose-based materials employing this same photosensitizer; the higher levels of photodynamic inactivation achieved here with PAN-Por(+) are likely due to the combined effects of higher photosensitizer loading and a greater surface area imparted by the use of nanofibers. These results demonstrate the potential of photosensitizer-embedded polyacrylonitrile nanofibers to serve as scalable scaffolds for anti-infective or self-sterilizing materials against both bacteria and viruses when employing a photodynamic inactivation mode of action.
Project description:Transparent and flexible electrodes are widely used on a variety of substrates such as plastics and glass. Yet, to date, transparent electrodes on a textile substrate have not been explored. The exceptional electrical, mechanical and optical properties of monolayer graphene make it highly attractive as a transparent electrode for applications in wearable electronics. Here, we report the transfer of monolayer graphene, grown by chemical vapor deposition on copper foil, to fibers commonly used by the textile industry. The graphene-coated fibers have a sheet resistance as low as ~1?k? per square, an equivalent value to the one obtained by the same transfer process onto a Si substrate, with a reduction of only 2.3 per cent in optical transparency while keeping high stability under mechanical stress. With this approach, we successfully achieved the first example of a textile electrode, flexible and truly embedded in a yarn.
Project description:Environmental DNA (eDNA) is one of the fastest developing tools for species biomonitoring and ecological research. However, despite substantial interest from research, commercial and regulatory sectors, it has remained primarily a tool for aquatic systems with a small amount of work in substances such as soil, snow and rain. Here we demonstrate that eDNA can be collected from air and used to identify mammals. Our proof of concept successfully demonstrated that eDNA sampled from air contained mixed templates which reflect the species known to be present within a confined space and that this material can be accessed using existing sampling methods. We anticipate this demonstration will initiate a much larger research programme in terrestrial airDNA sampling and that this may rapidly advance biomonitoring approaches. Lastly, we outline these and potential related applications we expect to benefit from this development.
Project description:Textile electronics are poised to revolutionize future wearable applications due to their wearing comfort and programmable nature. Many promising thermoelectric wearables have been extensively investigated for green energy harvesting and pervasive sensors connectivity. However, the practical applications of the TE textile are still hindered by the current laborious p/n junctions assembly of limited scale and mechanical compliance. Here we develop a gelation extrusion strategy that demonstrates the viability of digitalized manufacturing of continuous p/n TE fibers at high scalability and process efficiency. With such alternating p/n-type TE fibers, multifunctional textiles are successfully woven to realize energy harvesting on curved surface, multi-pixel touch panel for writing and communication. Moreover, modularized TE garments are worn on a robotic arm to fulfill diverse active and localized tasks. Such scalable TE fiber fabrication not only brings new inspiration for flexible devices, but also sets the stage for a wide implementation of multifunctional textile-electronics.
Project description:Assembling thermoelectric modules into fabric to harvest energy from body heat could one day power multitudinous wearable electronics. However, the invalid 2D architecture of fabric limits the application in thermoelectrics. Here, we make the valid thermoelectric fabric woven out of thermoelectric fibers producing an unobtrusive working thermoelectric module. Alternately doped carbon nanotube fibers wrapped with acrylic fibers are woven into ?-type thermoelectric modules. Utilizing elasticity originating from interlocked thermoelectric modules, stretchable 3D thermoelectric generators without substrate can be made to enable sufficient alignment with the heat flow direction. The textile generator shows a peak power density of 70?mWm-2 for a temperature difference of 44?K and excellent stretchability (~80% strain) with no output degradation. The compatibility between body movement and sustained power supply is further displayed. The generators described here are true textiles, proving active thermoelectrics can be woven into various fabric architectures for sensing, energy harvesting, or thermal management.
Project description:The analysis of microplastics in sediments, soils or beach samples is commonly paired with a separation step to enrich microplastics or to remove non-plastics, respectively. Those steps are often very time consuming and are performed in presence of high concentrated solvents. The latter are also suspected to corrode or decompose the analyte particles, which hamper further identification processes. This paper describes a new fast and effective microplastics separation apparatus for analytical issues that was based on hydrophobic adhesion of microplastics and fine air bubbles. The presented prototype could successfully enrich over 90 %wt of 30ppmw microplastics in 200?g sand in 20?min. Additionally, it could be demonstrated that the new separation technique was very suitable for further microplastics identification by FTIR microscopy. In this context, a sample with different polymers and matrix components was analyzed and the results were presented within this article. •Microplastics were enriched selectively by hydrophobic adhesion.•No additional chemicals except water and air were used.•Separation took only 20?min and 90 %wtof microplastics were recovered.
Project description:Tensan silk, a natural fiber produced by the Japanese oak silk moth ( Antherea yamamai, abbreviated to A. yamamai), features superior characteristics, such as compressive elasticity and chemical resistance, when compared to the more common silk produced from the domesticated silkworm, Bombyx mori ( B. mori). In this study, the "structure-property" relationships within A. yamamai silk are disclosed from the different structural hierarchies, confirming the outstanding toughness as dominated by the distinct mesoscale fibrillar architectures. Inspired by this hierarchical construction, we fabricated A. yamamai silk-like regenerated B. mori silk fibers (RBSFs) with mechanical properties (extensibility and modulus) comparable to natural A. yamamai silk. These RBSFs were further functionalized to form conductive RBSFs that were sensitive to force and temperature stimuli for applications in smart textiles. This study provides a blueprint in exploiting rational designs from A. yamanmai, which is rare and expensive in comparison to the common and cost-effective B. mori silk to empower enhanced material properties.