Textile Carrier Research Articles

Biomimetic fiber of PVDF@Ag enabling the multimodal sensing for biomechanics and biomolecules integrated by textile carrier

Intelligent wearables with integrated biomechanics and biomolecule multimodal sensing systems are crucial for personalized healthcare. However, the modes of action of biomechanics and biomolecule sensing work in different ways. Hence, a method for manufacturing biomimetic fibers made of polyvinylidene fluoride (PVDF)@silver (Ag) is initially devised, and a textile carrier serves as a link for multimodal sensing of biomechanics and biomolecules. PVDF nanofiber membranes are created using a one-step electrospinning process. Next, by lowering the silver ion’s reduction potential, compact and homogenous Ag nanoparticles (NPs) are formed in-situ on the high-curvature PVDF fibers. Consequently, a PVDF@Ag fiber membrane with a piezoelectric response and a localized surface plasmon resonance (LSPR) effect is created, making it suitable for wearable sensors that can detect secreta molecules as well as muscle movements. PVDF@Ag fiber is twisted, taking inspiration from the spiral structure of butterfly antennae. Compared to untwisted, twisted PVDF@Ag fiber, this produces a surface-enhanced Raman scattering (SERS) output signal that is more stable and can resist for signal attenuation caused by tensile deformation during wearable sensing. The “fingerprint” spectra of SERS enable noninvasive extraction and detection of secretion signals at sweat and respiration. Additionally, a plausible correlation between the range of secretions produced and health-related data is examined. Additionally, the integrated PVDF@Ag by polyester fabric exhibits superior air permeability, moisture absorption, and antimicrobial properties. And, this multimodal sensing mechanism has an algorithm implanted with deep learning support. All things considered, the PVDF@Ag fiber functions as a bridge between biomolecules and biomechanics, which is essential for applications involving wearable healthcare management.

Use of Rotary Ultrasonic Plastic Welding as a Continuous Interconnection Technology for Large-Area e-Textiles

For textile-based electronic systems with multiple contacts distributed over a large area, it is very complex to create reliable electrical and mechanical interconnections. In this work, we report for the first time on the use of rotating ultrasonic polymer welding for the continuous integration and interconnection of highly conductive ribbons with textile-integrated conductive tracks. For this purpose, the conductive ribbons are prelaminated on the bottom side with a thermoplastic film, which serves as an adhesion agent to the textile carrier, and another thermoplastic film is laminated on the top side, which serves as an electrical insulation layer. Experimental tests are used to investigate the optimum welding process parameters for each material combination. The interconnects are initially electrically measured and then tested by thermal cycling, moisture aging, buckling and washing tests, followed by electrical and optical analyses. The interconnects obtained are very low ohmic across the materials tested, with resulting contact resistances between 1 and 5 mOhm. Material-dependent results were observed in the reliability tests, with climatic and mechanical tests performing better than the wash tests for all materials. In addition, the development of a heated functional prototype demonstrates a first industrial application.

Effect of using alternate elastic and non-elastic yarns in warp on shrinkage and stretch behavior of bi-stretch woven fabrics

Stretch woven fabrics are known for their elastic and recovery properties. To date, they found many interesting applications from simple jeans to complex fabric structures with functional properties for example bi-stretch auxetic woven fabrics, compressions garments and stretchable textile carriers for healthcare applications. Many studies have been carried out on the physical, mechanical and comfort properties of stretchable knitted and woven fabrics. However, to identify combination of yarns with different stretch properties and other design parameters required to meet multiple objectives in the production and usage of bi-stretch woven fabrics is an area that has been taken up by fabric scientists recently. This study compared the effect of using elastic yarns and alternate elastic and non-elastic yarns in warp on the properties of bi-stretch woven fabrics while using elastic yarns in weft direction. It was found that shrinkage of the fabrics made of elastic yarns was higher along the warp direction as compared to that in weft direction due to shrinkage balancing effect; however, in case of fabrics made of alternate elastic and non-elastic yarns in warp the shrinkage behavior was exact opposite. The comparison of shrinkage for different weave patterns revealed that satin had the highest shrinkage followed by twill and plain, due to least number of interlacements in satin among these three patterns.

Silver nanoparticles with vanadium oxide nanowires loaded into electrospun dressings for efficient healing of bacterium-infected wounds

Silver nanoparticles (AgNPs) have been widely recognised as effective antibacterial materials in textiles for enhancing wound healing. However, high loadings of AgNPs are toxic and expensive. Thus, it is ideal to prepare AgNPs in a favourable nanostructure for stable and effective conjugation with the textile carrier by selecting a reductant and stabiliser that contributes to the antibacterial effect. Here, silver nanoparticles/vanadium oxide nanowires (Ag/VOx NWs) were prepared via a one-step reduction strategy using vanadium oxide quantum dots (VOx QDs) as both the reductant and stabiliser. VOx QDs possess antibacterial properties, which aid in minimising the applied silver content while enhancing bactericidal performance. Silver can self-aggregate into nanoparticles as well as promote the formation of vanadium oxide nanowires (VOx NWs). Accordingly, the Ag/VOx NWs exhibited remarkable antibacterial effects against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The nanowire structure of the Ag/VOx NWs was favourable for effective loading into a sodium alginate (SA) gel fabric to form a wound dressing. The effective loading of Ag/VOx NWs on SA was conducive to the complete dispersion of the bacteriostatic agent and enhanced the antibacterial activity of AgNPs. The wound dressing efficiently suppressed the growth of wound bacteria and promoted wound healing in vivo.

Effects of Composite Coatings Functionalized with Material Additives Applied on Textile Materials for Cut Resistant Protective Gloves.

The objective of the present work was to evaluate the effects of different types of particles added to a polymer paste applied onto a textile carrier on the cut resistance of the resulting material. Knitted aramid textile samples were coated in laboratory conditions using a polymer paste that was functionalized with 12 types of reinforcing particles of different chemical compositions and size fractions. Cut resistance was tested in accordance with the standard EN ISO 13997:1999 and the results were subjected to statistical analysis. The effects of additive particles on the microstructure of the polymeric layer were assessed by means of scanning electron microscopy. The type and size of the particles affected the cut resistance of the functionalized knitted fabric. They were also found to change the morphology of the porous structure. Composite coatings containing the smallest additive particles exhibited the best cut resistance properties.

Application of Warp Knit Spacer Fabrics in Tissue Engineering

Mesenchymal stem cells (MSCs) possess huge potential for regenerative medicine. For tissue engineering approaches, sca_olds and hydrogels are routinely used as extracellular matrix (ECM) carriers. The present study investigated the feasibility of using textile-reinforced hydrogels with adjustable porosity and elasticity as a versatile platform for soft tissue engineering. A warp-knitted poly (ethylene terephthalate) (PET) sca_old was developed and characterized with respect to morphology, porosity, and mechanics. The textile carrier was infiltrated with hydrogels and cells resulting in a fiber-reinforced matrix with adjustable biological as well as mechanical cues. Finally, the potential of this platform technology for regenerative medicine was tested on the example of fat tissue engineering. MSCs were seeded on the construct and exposed to adipogenic differentiation medium. Cell invasion was detected by two-photon microscopy, proliferation was measured by the PrestoBlue assay. Successful adipogenesis was demonstrated using Oil Red O staining as well as measurement of secreted adipokines. In conclusion, the given microenvironment featured optimal mechanical as well as biological properties for proliferation and di_erentiation of MSCs. Besides fat tissue, the textile-reinforced hydrogel system with adjustable mechanics could be a promising platform for future fabrication of versatile soft tissues, such as cartilage, tendon, or muscle.

Genipin-mediated immobilization of glucose oxidase enzyme on carbon felt for use as heterogeneous catalyst in sustainable wastewater treatment

Enzyme immobilization is necessary process to improve the bioactivity and stability of the biocatalyst. In this study, glucose oxidase (GOx) enzyme was immobilized on plasma-treated fibrous carbon felt as a textile carrier to produce a heterogeneous catalyst. Genipin, as a naturally occurring crosslinker, that has less cytotoxicity than conventional crosslinkers, was used in the enzyme immobilization process. UV-Vis and FTIR spectra confirmed the crosslinking reaction between genipin and the primary amines of GOx enzyme, by forming blue-pigmented aggregates. GOx relative activity after crosslinking and immobilization on the carbon felt was maintained up to 40%, with stability in performance up to 6 cycles for the plasma treated carbon, while maintaining their bio-electro-activity as shown from cyclic voltammetry scans (CV). The obtained heterogeneous catalysts have been tested for use in sustainable wastewater treatment of Remazol Blue RR (RB) dyestuff by means of Bio-Fenton (BF) and enzymatic Bio-electro-Fenton (BEF) processes. The produced samples resulted in high color removal efficiency, up to 93% discoloration of (RB) for the first use in (BF) process in 3 h. Meanwhile, enzymatic (BEF) process resulted in up to 34% of COD removal, with simultaneous power density generation up to 0.16 ± 0.01 μW.cm−2 at a current density of around 10 ± 2 μA.cm−2 in 12 h. These results highlight the importance of genipin as a bio-based crosslinker for enzymes, and the potential use in both (BF) and (BEF) as sustainable approaches for wastewater treatment and as a step towards zero-energy degradation of organic matter.

Immobilization of peroxidase on textile carrier materials and their application in the bleaching of colored whey

Textiles represent promising support materials for enzymes. The goal of the present work was to investigate the immobilization of commercial peroxidase on a polyester needle felt and the repeated use in the gentle degradation of norbixin in whey from dairy cheese as a practical application. High enzyme loads were obtained by a 2-step immobilization procedure. First, the number of functional groups on the textile surface was increased by a modification with amino-functional polyvinylamine. Second, the enzyme was immobilized by using 2 types of crosslinking agents. Due to the iron content of peroxidase, inductively coupled plasma-optical emission spectrometry was used for the quantitative determination of the enzyme load on the textile. The enzyme activity was evaluated using common 2,2'-azino-di-(3-ethylbenzthiazoline-6-sulfonic acid) assay for peroxidases. By the variation of enzyme input and crosslinker concentration, a maximal enzyme load of 80 mg/g of textile was achieved, and a maximum specific activity of 57 U/g of textile. For the visualization of the enzyme on the fiber surface, fluorescence microscopy as well as scanning probe microscopy were used. The immobilized peroxidase showed significant activity, even after 50 reuse cycles. In addition, the potential of the new support and enzyme combination in commercial whey bleaching was demonstrated successfully on a 10-L scale.

Singlet-Oxygen Generation by Peroxidases and Peroxygenases for Chemoenzymatic Synthesis.

Singlet oxygen is a reactive oxygen species undesired in living cells but a rare and valuable reagent in chemical synthesis. We present a fluorescence spectroscopic analysis of the singlet‐oxygen formation activity of commercial peroxidases and novel peroxygenases. Singlet‐oxygen sensor green (SOSG) is used as fluorogenic singlet oxygen trap. Establishing a kinetic model for the reaction cascade to the fluorescent SOSG endoperoxide permits a kinetic analysis of enzymatic singlet‐oxygen formation. All peroxidases and peroxygenases show singlet‐oxygen formation. No singlet oxygen activity could be found for any catalase under investigation. Substrate inhibition is observed for all reactive enzymes. The commercial dye‐decolorizing peroxidase industrially used for dairy bleaching shows the highest singlet‐oxygen activity and the lowest inhibition. This enzyme was immobilized on a textile carrier and successfully applied for a chemical synthesis. Here, ascaridole was synthesized via enzymatically produced singlet oxygen.

Warp-Knitted Spacer Fabrics: A Versatile Platform to Generate Fiber-Reinforced Hydrogels for 3D Tissue Engineering.

Mesenchymal stem cells (MSCs) possess huge potential for regenerative medicine. For tissue engineering approaches, scaffolds and hydrogels are routinely used as extracellular matrix (ECM) carriers. The present study investigated the feasibility of using textile-reinforced hydrogels with adjustable porosity and elasticity as a versatile platform for soft tissue engineering. A warp-knitted poly (ethylene terephthalate) (PET) scaffold was developed and characterized with respect to morphology, porosity, and mechanics. The textile carrier was infiltrated with hydrogels and cells resulting in a fiber-reinforced matrix with adjustable biological as well as mechanical cues. Finally, the potential of this platform technology for regenerative medicine was tested on the example of fat tissue engineering. MSCs were seeded on the construct and exposed to adipogenic differentiation medium. Cell invasion was detected by two-photon microscopy, proliferation was measured by the PrestoBlue assay. Successful adipogenesis was demonstrated using Oil Red O staining as well as measurement of secreted adipokines. In conclusion, the given microenvironment featured optimal mechanical as well as biological properties for proliferation and differentiation of MSCs. Besides fat tissue, the textile-reinforced hydrogel system with adjustable mechanics could be a promising platform for future fabrication of versatile soft tissues, such as cartilage, tendon, or muscle.

Large-Area Carbon Nanotube-Based Flexible Composites for Ultra-Wide Range Pressure Sensing and Spatial Pressure Mapping.

Flexible pressure sensors are of broad interest for applications including human-machine interfaces, wearable electronics, and object/motion detection. However, complexities associated with constituent materials, fabrication processes, sensing mechanisms, and hardwiring often hinder the large-scale applications of using high performance pressure sensors reported in the literature. Here we demonstrate a large-area, highly flexible, conformable, and mechanically robust pressure sensor using a silicone elastomer with an embedded nonwoven textile carrier coated with carbon nanotubes. The selected silicone polymer allows through-thickness deformability of the sensor while the high modulus textile carrier ensures in-plane stiffness and stability. The sensor has an initial electrical conductivity of 4.4 ± 0.38 S/m and is fabricated using a straightforward dip coating and polymer infusion process and can be easily scaled-up for large-scale applications. On the basis of its hierarchical composite structure, this piezoresistive pressure sensor possesses extremely high resilience under compression, a repeatable monotonic positive pressure correlation, and an ultrawide elastic working range (5.5 ± 0.5 MPa) that can be segmentally linearized. A true two-dimensional modality for spatial pressure mapping is realized by utilizing electrical impedance tomography (EIT) and demonstrated to yield conductivity maps that can estimate the location, shape, and amplitude of both localized and distributed pressure with simple contact areas.

Synthesis of a Highly Chained Polymeric Connecting in the Structure of a Multilayered Package for Garments

When using lightweight fabrics of costume-dress assortment for manufacture of clothes, the most challenging problem is to correlate changes in properties of shell fabric and fusible interlining during its transformation from flat to volumetric state. Developed the reinforced interlining materials capable of forming in conjunction with the shell fabric composites, possessing optimum shaping characteristics. They are easily shaped, and after a final wet-heat treatment they obtain required rigidity and elasticity values, thus ensuring that volumetric shape of a garment will be preserved in the process of wearing it by a user. The technology realizes original methods of selecting precision values for elastic-deformation properties in the laminate of shell fabric and an interlining by forming in a duplicating cloth 3D self-organizing structures of a reinforcing polymer-fibrous composite. It was proved that there is a chemical interaction between acrylate copolymers and polyamide adhesive, discretely distributed on the surface of interlinings. This ensures the formation of a three-dimensional reinforcing structures of a unique bristle-like shape, encrusting the surface of the fibers and penetrating into their nanoporous system. The required values for elastic-deformation properties of polymer-fibrous composite materials for various kinds of textile carriers can be found by changing topology of applying polymeric modifiers and conditions of copolymerization. A wide range of variation in elastic-deformation properties makes it possible to adapt quickly the assortment of interlining materials to the individual customer requirements taking into consideration the purpose of the manufactured clothing and characteristics of the shell materials.

MODIFICATION OF POLYESTER FIBERS TO CREATE COMPOSITE MATERIALS WITH ADJUSTABLE RIGIDITY

Research aims at experimental study of an effective method of creating polymer-fiber composite materials with a comb structure of an interfacial layer. To change the surface micro-relief of polyester fiber method of surface saponification in the presence of a quaternary ammonium compound was used. This method provides localized hydrolysis reacting of polymer to form dotted etch wells. Fiber modification allows synthesizing comb polymer chains of the binder with the penetration of the lateral branches into the formed pore spaces of the textile carrier. Condition of polyester fiber after saponification estimated by indices: a loss of fiber mass, specific breaking load of the material, the content of carboxyl groups, the sorption of acrylic dispersion. The criterion for the rapid assessment of the quality of the fiber modification to change the micro-relief of its surface can serve the magnitude of the fiber mass loss, which must not exceed 3 %. Estimating the size of the formed voids was carried out according to the nitrogen adsorption data using a sorption analyzer NOVA 1200e. In moderate alkaline hydrolysis conditions, the main increase in the internal free volume provides mesopores with a diameter of 35...40 nm. The formations of a sub microscopic size 7...8 nm are the most numerous. Assessment of nanosized condition of reinforcing polymer dispersion by dynamic light scattering method allows recommending the necessary depth of polyester fiber hydrolysis to ensure the effects of the composite material stiffness controlled increase in 10...16 times.

In-Line Integration of Sensors in Thermoplastic Composite Structures Using Novel Continuous Orbital Winding Technology

Currently there is a great demand for energy and resource efficient and also function integrating manufacturing processes. Therefore, suitable technologies and corresponding foundational researches are being pursued in the federal cluster of excellence “MERGE Technologies for Multifunctional Lightweight Structures” at the Technische Universität Chemnitz. A part of this project is the development of the continuous orbital winding (COW) technology including the goal of a large-scale process used for special fiber-reinforced thermoplastic semi-finished products. This method is an inverted winding process. The winding core needs to perform only the feed motion. Furthermore, this allows synchronization to upstream and downstream process chains.Due to the modular structure of the machine concept, it is possible to integrate a sensor system during production without interrupting the process. For this purpose, a textile carrier tape with integrated electrically conductive fibers and applied sensors is embedded. Various silicon sensors, e.g. acceleration, pressure or stress sensors are applied by micro-injection molding. A so-called “interposer” is used as an electrically adapter between the microstructures of the sensor system and the mesostructures of the textile.In this article, basic investigations for the continuous processing of semi-finished thermoplastic structures and the integration of sensors are presented. It is intended to determine the bonding properties, possible structural thickening by the sensors and the resistance of the sensor systems and its electronic components to the process conditions.In summary, investigations are carried out to determine the parameters of the machine system as well as to determine the optimum processing conditions for the application of additional elements.

Strategies for permanent immobilization of enzymes on textile carriers

The economical use of expensive enzymes in chemical synthesis can be improved by the immobilization of the catalyst on a suitable support material. Textile fabrics made of polyester, polyamide, or cotton represent comparatively inexpensive alternative carrier materials in contrast to conventional supports. Textile‐inherent advantages like its flexible and lightweight construction allow the use in reactors of arbitrary geometry, a quick separation from the reaction liquor, and the generation of residue‐free product. A low preparative and economical expense is needed to prepare fabrics with high enzyme loads (20–70 mg enzyme/g textile carrier), high relative activity (up to 20%) and excellent permanence against enzyme desorption as well. In this study, we present different strategies for the covalent fixation of enzymes on fiber forming polymers such as photochemical grafting, the use of bifunctional anchor molecules, monomeric, and polymeric cross‐linking agents or specific enzyme modification for direct immobilization. In addition, we compare the strategies in terms of load, catalytic activity, and reusability. All presented immobilization methods yield products, which exhibit a considerable activity even after twenty recycling steps. In conclusion, we have successfully identified textiles as alternative, new and promising low cost carrier materials for enzymes.

Failure modes of conducting yarns in electronic-textile applications

Integration of electronic functionalities into textiles adds to the value of textiles. It allows measuring, detecting, actuating and treating or communicating with a body or object. These added values can render the smart textiles very useful, fun, supporting, protecting or even lifesaving. It is, however, important for the comfort, acceptance and functionality to have integration of electronics as unobtrusive as possible. One elegant unobtrusive method of integration is to have circuitry included in the textile and mount components to this circuitry. Conducting yarns introduced by weaving, knitting or embroidery are attractive candidates to compose the circuitry as they do not disturb the textile nature of the system and are processable by the mentioned conventional textile technologies. In the case that these smart textiles are worn by humans under dynamic circumstances, the system is exposed to mechanical stress. In this paper we report the results of studies on the failure modes of Ag-coated nylon yarns, which are applied on textile carriers by means of stitching or soutache embroidery. The test methods varied in combinations of mechanical stress, such as shearing, bending and tension, and support to better understand the process of deterioration of the yarns when these are mechanically stressed. The delamination of the Ag coating from the yarns leads to unstable resistance values in non-static conditions. The mechanical forces, such as shearing, bending and tension, cause progressively more damage to the filaments of the yarns. This leads to a reduction of the electrical conductivity.

Validation Of Radiation Sterilization Dose For Proteases Immobilized On Aldehyde-Containing Textile Carriers

The main objective of this work is to establish the parameters of radiation sterilization for three proteolytic enzymes (papain, trypsin and subtilisin) immobilized on aldehyde-containing textile carriers in terms of the development of new biomaterials – wound dressings with debridement effect. This paper describes the steps taken to validate a low dose sterilization process by following the Method 2A defined in ISO 11137. The content of aldehyde groups in the used modified cellulose carriers is 0.798  0.002 mmol/g. After immobilization and freeze-drying of the respective enzyme, all experimental variants demonstrated proteolytic activity in the following ranges: Variant 1 (immobilized papain) 47.641.73 U/g; Variant 2 (immobilized trypsin) 84.571.45 U/g; Variant 3 (immobilized subtilisin) 55.53 3.46 U/g. The obtained results for enzyme activity made it possible to determine the dose of 30 kGy as the maximum acceptable dose for all experimental variants biomaterials. The minimal doses necessary to achieve sterilization at SAL of 10 -6 are respectively: variant 1 (immobilized papain) 16.0 kGy; variant 2 (immobilized trypsin) 15.2 kGy and variant 3 (immobilized subtilisin) 12.1 kGy. These low terminal doses provide effective bactericidal coverage and very likely have minimal impact on the properties of the biomaterials. For all three variants the proteolytic activity remains above 90% of the initial value.

Medical textile and hydrogel materials for targeted delivery of drugs in oncological practice

Article is devited to the use of textile technologies for creation of new types of medical materials and textile-based hydrogels with drugs, secured their directed controlled and prolonged delivery to the site of lesions in cancer patients. The application of textile printing technology has been substantiated. The following aspects have been studied: the role of textile carrier — the matrix for the polymer and drug, teological characteristics of the polymers-thickeners, mass transfer of drugs into the environment, the antioxidant activity of the drugs used for the creation of medical materials to improve the efficiency of treatment during the radiation therapy.

Study on Activated Sludge Properties of A/A/O Combined Membrane Bioreactor during Startup Period

To improve treatment performance and alleviate membrane fouling, the physical and biological properties of sludge in combined MBR which divided into anoxic, anaerobic and aerobic zone were studied. During initial startup period, the sludge in A/A/O combined MBR was suspended growth, after textile carrier package, the sludge was suspended and fixed growth. The biomass analysis showed that with the increase of operation time, MLVSS/MLSS decreased from 0.93 to 0.72 which certified that high MLSS concentration caused biomass growth slow gradually, while packing textile carrier could supply attached biomass which maximum value was 0.18g/cm(3777.8mg/L). Meanwhile, high MLSS concentration also resluted in high sludge viscosity which could reach to 35.42mPa•s and decreased sludge activity. Particle size anaylisis showed that shear stress of aeration made the sludge flocs smaller than conventional activated sludge process. All the sludge properties which had been analysis in this study showed A/A/O combined MBR had great difference from conventional MBR process, and some parameters could be used for membrane fouling control in A/A/O combined MBR for wastewater treatment project.

Cell Immobilization with Textile Carriers for TA Biodegradation

Fabrics provide an attractive alternative for cell immobilization carrier. In this study, the relationship of weave structure of fabrics and the effects of cell immobilization was investigated. Several kinds of fabrics with different weave structure were designed and produced acting as cell immobilization carrier. Adsorptive capacity of the textile carriers with different weave structure was measured and the biodegradation rate of TA by cells absorbed on textile carriers was also investigated. It is showed that adsorptive capacity and stability was significantly affected by weave structure of fabric carriers. The result also indicated that the ability to TA degradation was also improved by cell immobilization.