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As optoelectronic products continue to advance rapidly, the need for effective heat dissipation has become increasingly crucial due to the emphasis on miniaturization and high integration. The vapor chamber is widely used for cooling electronic systems as a passive liquid–gas two-phase high-efficiency heat exchange device. In this paper, we designed and manufactured a new kind of vapor chamber using cotton yarn as the wick material, combined with a fractal pattern layout of leaf veins. A comprehensive investigation was conducted to analyze the performance of the vapor chamber under natural convection circumstances. SEM showed that many tiny pores and capillaries were formed between the cotton yarn fibers, which are very suitable as the wick material of the vapor chamber. Additionally, experimental findings demonstrated the favorable flow and heat transfer characteristics of the cotton yarn wick within the vapor chamber, which makes the vapor chamber have significant heat dissipation capability, compared to the other two vapor chambers; this vapor chamber has a thermal resistance of only 0.43 °C/W at a thermal load of 8.7 W. In addition, the vapor chamber showed good antigravity capability, and its performance did not show significant changes between horizontal and vertical positions; the maximum difference in thermal resistance at four tilt angles is only 0.06 °C/W. This paper also studied the influence of vacuum degree and filling amount on the performance of the vapor chamber. These findings indicate that the proposed vapor chamber provides a promising thermal management solution for some mobile electronic devices and provides a new idea for selecting wick materials for vapor chambers. [ABSTRACT FROM AUTHOR]

[Display omitted] • The nZrS 3 @rGO nanocomposite modified conducting thread. • Ecofriendly, portable, cost-efficient biosensor for protein biomarker detection. • CKAP4 is a potential biomarker for detection of lung cancer at early stage. • Developed biosensor having excellent biosensing characteristics. Flexible technology in sensors have received much attention in monitoring of human health through various physiological indicators. Thus, it drawn a lot of interest in the development of flexible substrate for the diagnosis of various diseases via analysis of analytes. Present work focusses on the development of ecofriendly, portable, flexible, conducting thread (Th) and used as smart substrate for fabrication of biosensor towards ultrasensitive detection of the lung cancer biomarker (cytoskeleton-associated protein 4; CKAP4). The zirconium trisulfide-reduced graphene oxide nanocomposite and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) modified cotton thread based biosensor was fabricated via dip coating method. Next, successive immobilization of monoclonal antibodies of CKAP4 (anti-CKAP4) and bovine serum albumin (BSA) was performed via drop cast approach using fabricated electrode [nZrS 3 @rGO/PEDOT:PSS/Th]. The response of fabricated electrode (BSA/anti-CKAP4/ZrS 3 @rGO/PEDOT:PSS/Th) was recorded electrochemically versus CKAP4 concentration via chronoamperometry (CA). The results showed wider linear detection range of 6.25-800 pg mL−1, excellent sensitivity of 85.2 µA[log(pg mL−1)]-1cm−2 with good stability up to 42 days. The response of fabricated biosensor was supported by investigating response of CKAP4 biomarker present in patients of lung cancer (concentration as determined through enzyme-linked immunosorbent assay) and obtained results exhibited excellent correlation with that of standard samples. [ABSTRACT FROM AUTHOR]

• For the first time, a novel electronic capacitance acquisition system is developed for automatic characterization of capillary flow profile of liquid samples on μTADs. • This system was successfully used for viscosity measurement of mixture of glycerol and water, performance monitoring of chemical valves, and HCT measurement of whole blood samples. • This system is portable and easy to manufacture with a low cost, which suits well for point-of-care diagnostics. Capillary flow profile of liquid samples in porous media is closely related to the important properties of liquid samples, including the viscosity and the surface energy. Therefore, capillary flow profile can be used as an index to differentiate liquid samples with different properties. Fast and automatic characterization of capillary flow profile of liquid samples is necessary. In this work, we develop a portable and economical capacitance acquisition system (CASY) to easily obtain the capillary flow profile of liquid samples on microfluidic thread-based analytical devices (μTADs) by measuring the capacitance during the capillary flow. At first, we validate the accuracy of this method by comparing with the traditional method by video analysis in obtaining the capillary flow profiles in μTADs of cotton threads or glass fiber threads. Then we use it to differentiate liquid samples with different viscosity (mixture of water and glycerol). In addition, capillary flow profile on μTADs with chemical valves (chitosan or sucrose) can also be obtained on this device. Lastly, we show the potential of this device in measurement of hematocrit (HCT) of whole blood samples. This device can be used to catalog liquid biological samples with different properties in point-of-care diagnostics in the near future. [ABSTRACT FROM AUTHOR]

Wearable sensor patches for continuous or intermittent monitoring of biomolecules from body fluids are highly desired as a stretchable integrated platform conformable and attachable to the human body. However, realizing such integrated sensor patches is very challenging because of the difficulty of achieving full stretchability, controlling transport of the body fluid, and minimizing power consumption. In this study, a stretchable and self‐powered microfluidic‐integrated sensor patch comprising a stretchable non‐enzymatic fuel cell‐based sweat glucose sensor and a stretchable cotton thread‐embedded microfluidic device is demonstrated. To endow the fuel cell‐based glucose sensor with stretchability, the anode and cathode electrodes with catalytic nanoporous Au (NPG) and NPG coated with Pt nanoparticles (PtNPs@NPG), respectively, are formed on an omnidirectionally stretchable substrate with a three‐dimensional micropattern that can effectively absorb the stress generated during deformation. In addition, a stretchable microfluidic device made by embedding cotton thread into a polydimethylsiloxane (PDMS) channel for powerless constant absorption and sweat flow is integrated into the fuel cell structure. The fully stretchable microfluidic‐integrated self‐powered sensor patch demonstrates excellent continuous monitoring of the sweat glucose concentration. [ABSTRACT FROM AUTHOR]

We report on the development of an electrochemical sensor platform based on modified cotton fibers for the non-enzymatic detection of uric acid (UA), an important biomarker for gout disease. To create the flexible electrode, a cotton thread was coated with carbon ink as a pre-conductive layer prior to direct electrodeposition of AuNPs. Then, differential pulse voltammetry (DPV) was used to evaluate the sensor performances, and a linear detection range between 10 µM and 5.0 mM of uric acid was obtained. The sensor has a detection limit of 0.12 µM, which is sufficient for use in the patients suffering from gout disease which uric acid is higher than 4.46 mM. Furthermore, we found that the detection sensitivity of the platform was not affected by the presence of other physiological compounds present in human urine. The described platform has the potential for integration in a diaper hence enabling rapid detection and screening for gout disease. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel method for packaging cotton threads based μTADs is developed by encapsulating cotton threads into thermal contraction tube. • This package method can fabricate cotton threads based μTADs with complex 2D and 3D shapes, such as spiral shapes. • μTADs prepared by this package method are used for glucose and fibrinogen detection, plasma separation and HCT measurement. Passive microfluidic devices based on capillary force are popular choices for point-of-care diagnostics. Paper, threads and cloth have been used to fabricate these microfluidic devices. Here, we introduced a novel method for packaging microfluidic thread-based analytical devices (μTADs) by encapsulating cotton threads in thermal contraction tubes. This package method can help to increase convenience during practice. At first, we investigate the influence of this package method on the capillary flow behavior and water absorption capacity of cotton threads. Then, we show the possibility of this package method in preparing μTADs with complex shapes. Lastly, we successfully use μTADs based on this package method for applications in point-of-care diagnostics including glucose detection in urine, fibrinogen detection in blood plasma, and plasma separation from whole blood samples and hematocrit (HCT) measurement. The package method is promising in expanding the applications of μTADs in point-of-care diagnostics. [ABSTRACT FROM AUTHOR]

Influence of technological parameters of the upholstery seams in furniture. Based on the real problem of weak seams in covers of wooden furniture, a multifaceted analysis of the issue was performed. As a result, it was decided to carry out comparative laboratory strength tests of seams made with the use of various technological parameters. For the production of test samples, we used different yarn threads to find the best and sufficiently strong seams for used fabrics. The test results show that not only the thread and fabric used, but also the sewing technology parameters have a significant influence on the seam strength. Overall, these results indicate that to increase the seam strength, it is necessary to choose thread type B with very high strength and low elongation at break. This solution will minimize the risk of broken threads in case of deviation of material features and technological parameters, which can be variable in the long duration of large-scale production. [ABSTRACT FROM AUTHOR]

For sizing cotton yarn before weaving, a new composition based on a biodegradable polymer—collagen, has been proposed. The detected changes in the FT-IR spectra of the yarn coated with a collagen solution indicate the obvious formation of new intermolecular hydrogen bonds between the primary and secondary amino groups of the collagen and the cellulose hydroxyl groups. The formation of such bonds contributed to the strengthening of the collagen film on the surface of cotton threads. SEM studies have shown a significant improvement in the microstructure of threads and the morphology of fibers compared with threads not sized and sized with starch. When sizing with a collagen solution, the diameter of the threads decreases by 14%, when sizing with a starch solution—by 18%. In cases of collagen sizing, along with bonding, compaction, a longitudinal orientation of the fibers is observed. The diameter of the cellulose fibers sized with collagen is in the range of 12–15 microns. Unlike starch, which fills the interfiber spaces and even penetrates into individual tubular fibers, collagen is evenly located only on the surface of the fibers. Improving the microstructure and morphology of cellulose fibers and threads when sizing with a collagen-based composition leads to a reduction in the consumption of sizing agent, an increase in the linear density of threads by 15–20%, an increase in breaking load by 25–35%, and a decrease in elongation at break by 15–20%. [ABSTRACT FROM AUTHOR]

This paper reports the synthesis of conducting cotton thread strands obtained by dip coating in sodium dodecyl-benzene sulfonate (SDBS) surfactant with dispersed single-walled carbon nanotubes (SWCNT), as a promising candidate for energy storage applications. The effect of the dispersion and SDBS in the dissolved SWCNT solution was detected using field emission scanning electron microscopy (FE-SEM) and x-ray diffraction (XRD). XRD confirms that there was good dispersion of SWCNTs on the cotton thread strands obtained by doping employing ethylene glycol (EG) which lowers the corrugation of the cotton thread. FE-SEM images obtained at different magnifications show micro-fibril structure. Energy dispersive x-ray (EDX) analysis confirms the presence of only C, Na and S, ruling out the presence of any elemental impurity. A strong decrease from 3.587Ω to 0.01257Ω in electrical resistance was observed when the concentration of SWCNTs was increased from 0.008049 wt.% to 1.07269 wt.%, indicating that the SWCNTs induced conductive properties in the cotton thread strands. The study shows that sodium dodecyl benzyl sulfonate (SDBS) has the best dispersion of single-walled carbon nanotubes in water when used along with ethylene glycol. The results show that the coated threads can have great industrial applications as conduction wire substitute. [ABSTRACT FROM AUTHOR]

Cotton fiber is a biodegradable material that possesses properties such as high specific area, adjustable shape, and hygroscopicity. In this work, organic polymer was directly in situ grown on the surface of cotton thread and packed into a poly(ether ether ketone) tube for online in‐tube solid‐phase microextraction. The novel strategy solves the problems like high backpressure and tedious optimization process of normal monolithic polymer‐based in‐tube solid‐phase microextraction capillary. The quaternary ammonium typed ionic liquid of 1‐allyl‐methylimidazolium chloride, 4‐vinylbiphenyl, and ethylene dimethacrylate were co‐polymerized and in situ grown on the surface of cotton thread as extraction phase. The solid‐phase microextraction tube showed excellent performance for the extraction of three nonsteroidal anti‐inflammatory drugs including ketoprofen, naproxen, and flurbiprofen due to the strong ion exchange and hydrophobic interactions. After online coupling with a high‐performance liquid chromatography system by six‐port valve, the method was applied for the quantitative analysis of nonsteroidal anti‐inflammatory drugs in human plasma samples showing good enrichment performance (enrichment factor between 263 and 279), high sensitivity, good linearity, and good reproducibility. [ABSTRACT FROM AUTHOR]

A sensitive and portable on-thread pre-concentration and colorimetric detection method of copper ions was proposed. Commercial cotton thread was proposed as a solid sorbent for effectively extracting copper ions (Cu2+) from solution. The adsorbed Cu2+ was converted to Cu+ by ascorbic acid. The Cu+ on the threads was visualized by horseradish-peroxidase-catalyzed color changes of a chromogenic oxidized tetramethylbenzidine substrate. The adsorption of Cu2+ on the plasma- and Na 2 CO 3 -treated thread was verified by scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, and zeta potential characterization. The Cu+-induced dysfunction of HRP on the thread was verified by X-ray photoelectron spectroscopy. With optimized reaction conditions, the concentration-dependent colorimetric response plot was characterized, where the linear detection range was 2–400 nM and the detection limit was about 0.15 nM. Measurements of a group of possible interfering ions and spiked real-water samples demonstrated the good selectivity of the proposed method. The proposed on-thread pre-concentration and colorimetric detection offers a low-cost and effective alternative for detecting of copper ions in real applications. Unlabelled Image • Cotton thread was used as a low-cost, effective solid sorbent for copper ion extraction. • On-thread colorimetric detection of adsorbed copper was demonstrated. • Sensitive detection of copper was demonstrated by analyzing tap and lake water. [ABSTRACT FROM AUTHOR]

Development of wearable devices for in situ monitoring biological analytes in sweat has been fueled up in the past few years. Although microfluidic thread/paper-based analytical device (μTPAD) fulfills the requirements of wearable systems on flexibility and biocompatibility, it has not been employed as a sensing system for the in situ sweat analysis. In this work, we developed a wearable μTPAD containing a cotton thread and a functionalized filter paper for non-invasive, quantitative and in situ monitoring of human sweat glucose with the assistance of a smartphone. The oxygen plasma was applied to tailor the wicking property of the cotton thread. Amounts of enzymes and reagents on the filter papers were optimized to achieve the high-performance colorimetric sensing of glucose. The as-prepared device possesses a dynamic range of 50–250 μΜ and a detection limit of ~ 35 μΜ. Because of its great wearability and compatibility with conventional textile industry, the μTPAD was integrated with an arm guard to sensitively detect glucose in human sweat. This work may provide a low-cost, easy to use wearable device based on the cotton thread and filter paper for human sweat analysis. [ABSTRACT FROM AUTHOR]

In present work, we report an eco-friendly, flexible and highly conducting cotton thread (CT) as a smart substrate for the development of biosensing platform towards ultrasensitive detection of swine flu serum amyloid A (SAA) biomarker. The biosensor was fabricated by optimized coating of CT with poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) conductive ink followed by incorporation of nanodot zirconium trisulfide (nZrS 3) which helped in enhancing the electrochemical properties and improving stability of PEDOT:PSS polymeric film. The fabricated nZrS 3 /PEDOT:PSS/CT electrode was then used for sequential immobilization of monoclonal antibodies of SAA (anti-SAA) and bovine serum albumin (BSA). The synthesized nanomaterials and fabricated electrodes were characterized through X-ray diffraction, Fourier-transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy and contact angle analyser techniques. The electrochemical response of the fabricated smart thread based biosensor (BSA/anti-SAA/ZrS 3 /PEDOT:PSS/CT) was recorded against SAA using chronoamperometry technique which revealed superior sensitivity {30.2 μA [log (μg mL−1)]−1 cm−2}, excellent lower detection limit (0.72 ng mL−1) and prolonged shelf life up to 48 days. The response of the biosensor was also validated by analysing the electrochemical response of SAA spiked serum samples and the obtained results showed good correlation with that of standard samples. [ABSTRACT FROM AUTHOR]

Abstract A simple and sensitive device is presented based on the use of pencil-drawn paper based electrochemical detector placed at the end of a cotton thread fluidic channel in wall-jet configuration. This innovative and fast responding electroanalytical system can be adopted for both single and dual electrode electrochemical detection, this last achieved by applying two different potentials at two independent working electrodes drawn on the opposite faces of the paper based detector. Its performance was preliminarily optimized by adopting hexacyanoferrate(II) as probe species undergoing reversible electrochemical processes. These devices were then used for the single electrode detection of ascorbic acid in aqueous samples and the dual electrode detection of orthodiphenols in extra virgin olive oils (EVOOs). In fact, these devices enable hydrophilic orthodiphenols, typically present in EVOOs (extracted by a 80:20% v/v acetonitrile/water mixture), to be discriminated from hydrophilic monophenols instead present in almost all vegetable oils. Flow-injections runs were conducted by using a 0.01 M H 2 SO 4 + 0.5 KCl running electrolyte allowing the rapid and selective detection of hydrophilic orthodiphenols with satisfactory sensitivity and a low enough detection limit (2 μM). Different real samples of EVOOs and sunflower oils were analyzed. Abundant enough contents of orthidiphenols were found in EVOO samples, while no trace of these antioxidants was found in sunflower oils. Graphical abstract Image 1 Highlights • Paper based wall-jet electrochemical detectors coupled with cotton-thread fluidic systems are proposed. • A pencil drawing approach was used to construct electrochemical detectors. • Dual electrode configuration of electrochemical detectors enables detection of analytes with reversible behavior. • Simple and inexpensive methods for the detection of ascorbic acid and orthodiphenols are proposed. [ABSTRACT FROM AUTHOR]

Potentiometric sensing of ions with ion-selective electrodes (ISEs) is a powerful technique for selective and sensitive measurement of ions in complex matrices. The application of ISEs is generally limited to laboratory settings, because most commercially available ISEs and reference electrodes are large, delicate, and expensive, and are not suitable for point-of-use or point-of-care measurements. This work utilizes cotton thread as a substrate for fabrication of robust and miniaturized ISEs that are suitable for point-of-care or point-of-use applications. Thread-based ISEs selective for Cl−, K+, Na+, and Ca2+ were developed. The cation-selective ISEs were fabricated by coating the thread with a surfactant-free conductive ink (made of carbon black) and then coating the tip of the conductive thread with the ion-selective membrane. The Cl− ISE was fabricated by coating the thread with an Ag/AgCl ink. These sensors exhibited slopes (of electrical potential vs. log concentration of target ion), close to the theoretically-expected values, over four orders of magnitude in concentrations of ions. Because thread is mechanically strong, the thread-based electrodes can be used in multiple-use applications as well as single-use applications. Multiple thread-based sensors can be easily bundled together to fabricate a customized sensor for multiplexed ion-sensing. These electrodes require volumes of sample as low as 200 μL. The application of thread-based ISEs is demonstrated in the analysis of ions in soil, food, and dietary supplements (Cl− in soil/water slurry, K+ and Na+ in coconut water, and Ca2+ in a calcium supplement), and in detection of physiological electrolytes (K+ and Na+ in blood serum and urine, with sufficient accuracy for clinical diagnostics). [ABSTRACT FROM AUTHOR]

Cotton thread has been proposed as a new, economically affordable material for the fabrication of microfluidic circuits for use in fast, low-cost, point-of-care diagnostic testing devices. In this work, chitosan, a biocompatible polymer, was used to modify cotton thread to improve its fluidic properties for microfluidic applications. Electrostatic-interaction-mediated adsorption of chitosan on alkaline-scoured thread can effectively increase thread’s solution hydrophilicity and wicking rate. Moreover, the proposed process conserves the thread’s hydrophilicity and fluidic properties even when stored for several months. As a microfluidic platform for enzymatic-reaction-associated colorimetric measurement, the suggested chitosan modification results in the accumulation of more analyte in the detection zone because of the improved flow rate, which enhances the colorimetric signal intensity. In this study, a glucose oxidase-mediated colorimetric glucose assay was demonstrated on a chitosan-modified microfluidic thread-based analytical device (μTAD). A linear range of 1-7.5 mM, a low detection limit of 0.2 mM, and a recovery rate between 93 and 98% was achieved in detecting glucose in artificial urine samples. [ABSTRACT FROM AUTHOR]

Infectious bronchitis virus (IBV), an avian coronavirus, significantly affects the performance of both the egg-laying and meat-type birds causing the foremost of economic loss in poultry industry. This paper aims to develop a rapid, low-cost, and sensitive biosensor for IBV detection by using molybdenum disulfide (MoS2). MoS2 is a 2-D nanosheet which has strong high fluorescence-quenching ability when applied to a dye-labeled antibody (Ab). In this paper, we developed an Ab-functionalized MoS2-based fluorescent immunosensor, which utilized the fluorescence resonance energy transfer (FRET) between the MoS2 and fluorescence dye during the Ab–antigen interaction. The assay was performed on a low-cost cotton thread-based microfluidic platform due to the good wicking property and flexibility. Upon the optimization of assay conditions, the immunosensor demonstrated remarkable sensitivity of 4.6\times 10^2 EID50 per mL and specificity with a dynamic linear response range of 102–106 EID50 per mL for IBV standard solutions. The developed immunoassay successfully detected the IBV spiked chicken serum with satisfactory results. The foregoing presents its potential application for on-farm detection. [ABSTRACT FROM PUBLISHER]

A new paper-based microfluidic device is fabricated on a piezoelectric substrate. A polydimethylsiloxane channel filled with cotton threads is mounted on the piezoelectric substrate with an interdigital transducer. A testing filter paper with dried reaction solution is coated on the end of the cotton thread. Sample solution is driven to the cotton thread channel and transported to testing area for microfluidic analysis. Red ink solution and color development reaction of starch are demonstrated for microfluidic operation and analysis. Results show that the linear velocity of microfluidic transportation in the cotton thread channel is 4.558 mm/s, and color development reaction of starch is successfully implemented. [ABSTRACT FROM AUTHOR]

A cost-effective assay for antioxidant using simple cotton thread combining paper based device with mobile phone detection has been investigated. Standard and sample solutions flow along a bunch of cotton thread treated with sodium hydroxide via microfluidic behaviors without external pumping. The analyte solution reacts with the reagents that have been immobilized on the paper strip fixed at the end of the cotton bunch. The developed platforms were used for the assays of total phenolic content and antioxidant capacity by employing Folin-Ciocalteu and 2, 2-diphenyl-1-picryhydrazyl (DPPH) respectively. Simple detection can be made by employing a mobile phone camera (iPhone 4S) with Image J or Photoshop for image processing and evaluation. Gallic acid was used as a reference standard in this work, as its polyphenol structures can be found in many plants. The total phenolic content is expressed as gallic acid equivalents (GAE) (mg/g material). Inhibition capacity is calculated by the equation: % I = [(I o – I s )/ I o ] × 100, where I s is the relative magenta intensity (CMYK mode) of sample, and I o the relative magenta intensity of DPPH•. IC 50 inhibition can be estimated from the graph and can be used for the antioxidant capacity consideration. Applications to the assay green tea samples were demonstrated. The total phenolic contents in the green tea samples were found to be 48–105 mg/g, with %RSD of less than 10 for that of higher 50 GAE mg/g and IC 50 values of the samples studied were 25–50 mg/L. The results obtained by the developed methods agree with that of the standard methods. [ABSTRACT FROM AUTHOR]

[Display omitted] • A thread-based microfluidic device with a NiS/GO modified carbon paste electrode was developed. • Low-cost and continuous method for urea electrochemical detection. • Urea detection in samples of artificial and natural saliva. Urea concentration is an essential indicator of various kidney diseases. The development of an effective method for detecting urea is still an important task. In recent years, microfluidic devices have become an attractive approach for constructing a novel urea analysis system because of their advantages such as less reagent and low sample consumption and high analysis speed. In this report, a cotton thread-based microfluidic electrochemical analysis device was developed for flow urea detection by 3D printing technology. Cotton thread was used as the microfluidic channel for sample flow and NiS/GO modified carbon paste electrode was worked as a urea sensor. The experimental results showed that the proposed microfluidic device provided a stable carrier fluid flow rate and a significant catalytic performance for the electrochemical oxidation of urea. The device allowed to detect urea in the concentration range from 0.1 mM to 6.0 mM with a detection sensitivity of 32.61 μA L mmol−1. In addition, the proposed method has been successfully applied to the detection of urea in human saliva samples by a non-enzymatic amperometry method. More importantly, the approach can be successfully applied to non-enzymatic amperometric detection of urea in human saliva samples. [ABSTRACT FROM AUTHOR]

The tear glucose analysis is an important alternative for the indirect, simple and less invasive monitoring of blood glucose levels. However, the high cost and complex manufacturing process of tear glucose analyzers combined with the need to exchange the sensor after each analysis in the disposable tests prevent widespread application of the tear in glucose monitoring. Here, we present the integration of a biosensor made by the electropolymerization of poly(toluidine blue O) (PTB) and glucose oxidase (GOx) with an electroanalytical microfluidic device of easy assembly based on cotton threads, low cost materials and measurements by microflow injection analysis (µFIA) through passive pumping for performing tear glucose analyses in a simple, rapid and inexpensive way. A high stability between the analyses (RSD = 2.54%) and among the different systems (RSD = 3.13%) was obtained for the determination of glucose, in addition to a wide linear range between 0.075 and 7.5 mmol L −1 and a limit of detection of 22.2 µmol L −1 . The proposed method was efficiently employed in the determination of tear glucose in non-diabetic volunteers, obtaining a close correlation with their blood glucose levels, simplifying and reducing the costs of the analyses, making the tear glucose monitoring more accessible for the population. [ABSTRACT FROM AUTHOR]

A novel cotton thread immunochromatographic assay device was successfully developed based on gold nanoparticles decorated carbon nanotube nanocomposite probe (CNT/GNPs). Squamous cell carcinoma antigen (SCCA), a protein biomarker related to lung cancer, was used as an analyte to demonstrate the principle of immunochromatograpgic assay on cotton thread biosensor. Results indicated that CNT/GNPs exhibited good stability and superior sensitivity comparing with individual carbon nanotubes as reporter probe. Under optimal conditions, the biosensor was capable of measuring 3.03 ng/mL SCCA which is 10 and 5000 folds more sensitive than previous reported CNT based lateral flow assay. The combination of CNT/GNPs nanocomposite probe with cotton thread based biosensor provide an alternative path for clinical diagnosis of other protein or nucleic acid biomarkers. [ABSTRACT FROM AUTHOR]

At present, endoscopy relies almost exclusively on optical microscopy and the accurate analysis such as MS interrogation is performed ex situ using biopsy. In this work, a novel probing system is developed to perform in situ and in vivo endoscopic mass spectrometry using a moving string for the sampling and transportation of material. A prototype of a mass spectrometric endoscope is constructed using an industrial endoscope and a commercial mass spectrometer. The sampling system consists of a moving cotton thread driven by motorized pulleys. When the target surface is touched by the sampling probe, the cotton thread “wipes” and transports the adhered sample to the ion source. Depending on the target analytes, desorption electrospray and atmospheric pressure chemical ionization sources are employed interchangeably for the desorption and ionization. The surface under analysis is not subjected to heat, organic solvents, high voltage or charged droplets. In situ endoscopic MS of a living mouse and surface analysis inside a volunteer subject's mouth are demonstrated. [ABSTRACT FROM AUTHOR]

Studies were conducted to see the seasonal population incidence of Dusky Cotton Bug (DCB), Oxycarenus hyalinipennis Costa at the Nuclear Institute for Agriculture & Biology (NIAB), Faisalabad during June, 2015. Data revealed that the incidence of DCB started in the second week of September and reached to the peak level in the first week of October. The population started to decline till first week of November at the termination of the crop. The DCB population recorded low on non-Bt compared to Bt cotton genotypes. The optimum temperature and humidity for DCB was recorded at 35.5 and 41 %, respectively. Moreover, a field bioassay study showed that the mean DCB population remained at 1.8 per boll on imidacloprid, whereas no DCB was recorded on chlorpyriphos after 96 hrs post treatment. [ABSTRACT FROM AUTHOR]

This paper describes a low-cost, sensitive, visual and rapid immunochromatographic assay method on cotton thread for carcinoembryonic antigen (CEA) detection by using novel carbon nanotube/gold nanoparticles (CNT/GNPs) nanocomposite reporter probe. CEA, a lung cancer protein biomarker, was used as analyte to demonstrate the principle of the immunochromatographic assay on cotton thread biosensor. In the presence of target CEA, the decreasing aggregation amount of CNT/GNPs nanocomposite reporter probes on the test zone induced directly readout by naked eye. Meanwhile, quantitative detection could be performed conveniently with a commercial available scanner. The performance with respect to sensitivity of the method was greatly improved by 2–3 magnitudes comparing with traditional gold nanoparticles (GNPs) or carbon nanotubes (CNTs) as reporter probe. Under optimal conditions, the biosensor was capable of detecting 2.32 ng/mL CEA (S/N ≥ 3) which is sensitive enough for clinical diagnosis. These results indicated the novel CNT/GNPs nanocomposite reporter probe based immunochromatographic assay on cotton thread is particularly suitable for point-of-care (POC) diagnostics in resource-limited regions. [ABSTRACT FROM AUTHOR]

The micro flow injection analysis (μFIA) is a powerful technique that uses the principles of traditional flow analysis in a microfluidic device and brings a number of improvements related to the consumption of reagents and samples, speed of analysis and portability. However, the complexity and cost of manufacturing processes, difficulty in integrating micropumps and the limited performance of systems employing passive pumps are challenges that must be overcome. Here, we present the characterization and optimization of a low cost device based on cotton threads as microfluidic channel to perform μFIA based on passive pumps with good analytical performance in a simple, easy and inexpensive way. The transport of solutions is made through cotton threads by capillary force facilitated by gravity. After studying and optimizing several features related to the device, were obtained a flow rate of 2.2 ± 0.1 μL s −1 , an analytical frequency of 208 injections per hour, a sample injection volume of 2.0 μL and a waste volume of approximately 40 μL per analysis. For chronoamperometric determination of naproxen, a detection limit of 0.29 μmol L −1 was reached, with a relative standard deviation (RSD) of 1.69% between injections and a RSD of 3.79% with five different devices. Thus, based on the performance presented by proposed microfluidic device, it is possible to overcome some limitations of the μFIA systems based on passive pumps and allow expansion in the use of this technique. [ABSTRACT FROM AUTHOR]

Cotton thread is promising in fabricating biosensors for diagnostic application due to its excellent characteristics. However, the enrichment of the capture molecules on a narrow zone of the cotton thread based biosensor is a big challenge because of its superhydrophilicity. Here, we report a simple, low-cost and accurate cotton thread based nucleic acid biosensor with temperature-dependent pattern. Liquid wax is used to fabricate temperature-dependent pattern to restrict the test zone in a narrow area. This biosensor enables visual and quantitative detection of target DNA by accumulation of gold nanoparticles (GNPs) on the test zone with a detection limits of 0.75 nM. In addition, the cotton thread based biosensor needs less sample than previous reported lateral flow strip and the sample solution wicks faster at the cotton thread which can lead to a shorter detection time. This simple, low-cost and fast detection method holds great potential to improve healthcare services in the developing regions. [ABSTRACT FROM AUTHOR]

At present, the topic of building high-performance, miniaturized and mechanically flexible energy storage modules which can be directly integrated into textile based wearable electronics is a hotspot in the wearable technology field. In this paper, we reported a highly flexible fiber-shaped electrode fabricated through a one-step convenient hydrothermal process. The prepared graphene hydrogels/multi-walled carbon nanotubes-cotton thread derived from natural cotton thread is electrochemically active and mechanically strong. Fiber-shaped supercapacitor based on the prepared fiber electrodes and polyvinyl alcohol-H 3 PO 4 gel electrolyte exhibits good capacitive performance (97.73 μF cm −1 at scan rate of 2 mV s −1 ), long cycle life (95.51% capacitance retention after 8000 charge-discharge cycles) and considerable stability (90.75% capacitance retention after 500 continuous bending cycles). Due to its good mechanical and electrochemical properties, the graphene hydrogels/multi-walled carbon nanotubes-cotton thread based all-solid fiber-shaped supercapacitor can be directly knitted into fabrics and maintain its original capacitive performance. Such a low-cost textile thread based versatile energy storage device may hold great potential for future wearable electronics applications. [ABSTRACT FROM AUTHOR]

The ZnO nanorods have been grown on the cotton threads with ZnO seed layer by an aqueous chemical growth method at the low reaction temperature. The ZnO nanorods can provide a good geometric structure to deposit Pt nanoparticles with uniform size by a facile ion sputtering method. The photocatalytic activity of the different lengths of cotton threads with ZnO nanorods were evaluated in the photocatalytic degradation of rhodamine 6G by a 10 W UV light irradiation. The ZnO/Pt core-shell nanorods revealed much higher photodegradation efficiency than ZnO nanorods or commercial TiO 2 nanopowders, which improved the separation of photogenerated electrons and holes. Furthermore, the reusability test can demonstrated that the ZnO/Pt core-shell nanorods on the cotton threads still maintained high photocatalytic activity over five cycles. The ZnO/Pt core-shell nanorods provide a facile, low cost, high surface-to-volume ratio, high photocatalytic efficiency, and high reusability, which shall be also promising in the decomposition of environment pollutants and reusing of wastewater treatment. [ABSTRACT FROM AUTHOR]

Fibriform supercapacitors (FSC) are promising energy storage devices for wearable electronics which require excellent durability and fabric-like wearable comfort. In this work, we successfully converted commercial cotton threads (CT) into electrically conductive and electrochemically active threads by introducing reduced graphene oxide (rGO) and carbon nanoparticles (CNPs) using a large-scale producible method (dip-coating combined with low-temperature vapour reduction). The rGO coated CT (rGO-CT) has impressive conductivity which is attributed to the wrapped rGO nanosheets and it is steady enough to tolerate washing process for a long time. After coated with CNPs, the conductivity of CNPs/rGO composites coated CT (CNPs/rGO-CT) has been enhanced tremendously. Meanwhile, the rGO nanosheets with implanted CNPs form the three-dimensional (3D) hierarchical nanostructures which provide abundant ion transmission channels. Furthermore, we have prepared the CNPs/rGO-CT based FSC, which exhibits high volumetric capacitance (3.79 mF cm −3 at 50 mV s −1 ), well cycling stability (95.23% capacitance retention after 10000 charge-discharge cycles), and excellent electrochemical stability (92.30% capacitance retention after 2000 bending cycles). Especially, the CNPs/rGO-CT based FSC maintains great capacitive performance when it was knitted into textile, thus making it meet the high performance requirements of energy storage devices for knittable and wearable electronics. [ABSTRACT FROM AUTHOR]

Effect of rotor type, rotor diameter, doffing-tube nozzle, and torque-stop on polyester/cotton rotor-spun yam hairiness have been studied. To model the hairiness of polyester/cotton blended yam, artificial neural networks and regression models have been used. The results show that there are significant differences in performance of network with different architectures and training algorithms. The network with two hidden layers has the best performance and can predict hairiness with high accuracy. Relative importance of input variables is studied with partial derivatives method based on the optimum network. The results indicate that rotor type and rotor diameter have the greatest and least effect on the blended yam hairiness. [ABSTRACT FROM AUTHOR]