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Abstract The use of microorganisms in biosorption is one of the most promising ways to remove trace amounts of heavy metal ions. Nevertheless, the enhancement of the successful removal of heavy metal ions by using different combinations of biosorbents is not generally guaranteed which leaves room to explore the application of the technique. In this study, the performance of free and immobilized forms of a yeast strain, Candida krusei (C. krusei), and calcium alginate (CaAlg) are evaluated for their ability to remove copper(II). Infrared spectroscopy, studies on the effects of pH and temperature, and kinetics and isotherm modelling are carried out to evaluate the biosorption. The infrared spectroscopy shows that the primary biosorption sites on the biosorbents are carboxylate groups. In addition, a higher pH and higher temperatures promote biosorption while a decline in biosorption ability is observed for C. krusei at 50 °C. The kinetics study shows that C. krusei, CaAlg and immobilized C. krusei (MCaAlg) conform with good correlation to pseudo-second order kinetics. MCaAlg and CaAlg fit well to the Langmuir isotherm while C. krusei fits well to the Temkin isotherm. From the experimental data, encapsulating C. krusei showed improved biosoprtion and address clogging in practical applications.

Abstract Based on a selection of 101 articles published from 2013 to 2022, this study systematically reviews the application of intelligent techniques and optimization algorithms in textile colour management. Specifically, the study explores how these techniques have been applied to four subfields within textile colour management: colour matching and prediction, colour difference detection and assessment, colour recognition and segmentation, and dye solution concentration and decolourization. Following an introduction to intelligent techniques and optimization algorithms in textile colour management, the study describes the specific applications of these techniques in the field over the past decade. Descriptive statistics are used to analyse trends in the use of these techniques and optimization algorithms, and comparative performances indicate the effectiveness of the techniques and algorithms. The study finds that the primary intelligent techniques used in the field of textile colour management include artificial neural networks (ANN), support vector machines (SVM) such as SVM, LSSVM, LSSVR, SLSSVR, FWSVR, fuzzy logic (FL) and adaptive neuro-fuzzy inference systems (ANFIS), clustering algorithms (e.g., K-means, FCM, X-means algorithms), and extreme learning machines (ELM) such as ELM, OSLEM, KELM, RELM. The main optimization algorithms used include response surface methodology (RSM), genetic algorithms (GA), particle swarm optimization (PSO), and differential evolution (DE). Finally, the study proposes a comparison of the performance of intelligent techniques and optimization algorithms, summarizes the relevant research trends, and suggests future research opportunities and directions, besides stating the limitations of this paper.

Cellulosic fibres provide a very agreeable environment for growth of bacteria due to large surfaces with high moisture absorbability. Therefore, the demand for an anti-microbial finish as an effective means of preventing disease transmission is high; it inhibits growth of or kills microorganisms on textile fabrics. This paper reports results of experiments where silver oxide (Ag2O) or zinc oxide (ZnO) was used as a catalyst with the halogenated phenoxy compound (Microfresh, MF) and a binder (Microban, MB) on cotton fabrics to improve treatment effectiveness and minimize its side effects. Anti-microbial-treated fabrics showed some new characteristic peaks in chemical structure as evaluated by Fourier Transform Infrared Spectroscopy. In an anti-microbial test, it was found that anti-bacterial activity increased as MF-MB chemical agents were applied to the fabrics. A noticeable result was that the metal oxide catalyst had a significant effect on enhancing the performance. Surface morphology of anti-microbial-treated cotton specimens showed roughened and wrinkled fabric surface with high deposition of the finishing agent, which had a lower breaking load and tearing strength resulting from side effects of the acidic treatment. However, the addition of the Ag2O catalyst was able to compensate for the reduction in tensile and tearing strength, and it is considered harmless for human skin.

Flammability properties of plasma pretreated cotton fabrics subjected to flame-retardant treatment were studied. Plasma pretreatment, using an atmospheric pressure plasma jet (APPJ), was applied to cotton fabrics to enhance material properties, while retaining inherent advantages of the substrates. An organic phosphorus compound (flame-retardant agent, FR) together with a melamine resin (crosslinking agent, CL) and phosphoric acid (catalyst, PA) were used. Titanium dioxide (TiO2) or nano-TiO2 was used as a co-catalyst for cotton fabrics to improve treatment effectiveness and minimize side effects. Surface morphology of plasma pretreated cotton specimens subjected to flame-retardant treatment showed a roughened and wrinkled fabric surface with high deposition of the finishing agent, caused by an etching effect of plasma and attack of acidic FR. Combustibility of FR-CL-PA-TiO2 and FR-CL-PA-Nano-TiO2 treated fabrics was evaluated by a 45° flammability test. FR-CL-PA-treated specimens showed superior flame-retardancy, which was further improved by plasma pretreatment and addition of metal oxide as a co-catalyst. However, in comparison with the control sample, flame-retardant-treated cotton specimens had lower breaking load and tearing strength, resulting from side effects of the crosslinking agent used, while plasma pretreatment might compensate for the reduction in tensile strength caused by flame-retardant agents. In addition, both plasma pretreatment and metal oxide co-catalyst added in the flame-retardant finishing improved the crosslinking process between FR and cotton fabric, minimizing formation of free formaldehyde and allowing the use of FR in industry.

Chitosan-based photocatalyst composites containing CdS nanocrystals with and without glutaraldehyde or epichlorohydrin cross-linking treatments were investigated and the catalyzed photodegradation of methyl orange in aqueous solution was examined. In addition, the effects of catalyst dosage, initial dye concentration, and initial pH of the dye solution on the photodegradation kinetics were investigated. In this study, the effect of initial solution pH was more important than other factors. The photocatalyst composite could remove 99% dye in 80 minutes at pH 4. The catalyst composite was characterized by using X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), fourier transform infrared (FT-IR), and visible reflectance spectroscopy. The dye removal mechanism of methyl orange involved an initial sorption process followed by photodegradation. The sorption process underwent the pseudo-second order kinetics, while photodegradation followed the Langmuir-Hinshelwood kinetics. Although the glutaraldehyde cross-linked chitosan enhanced the initial dye sorption, the epichlorohydrin cross-linked catalyst composite demonstrated a better overall dye removal performance, especially in the photodegradation step. Both chitosan encapsulated catalyst with and without epichlorohydrin cross-linking demonstrated the same pseudo-first order photodegradation kinetic constant of 0.026 min−1 and the same dye removal capacity. The catalyst composite could be reused but the photocatalytic activity dropped successively in each cycle.

This study used Bayesian Regulated Neural Networks (BRNN) with 10-fold cross-validation to accurately forecast fading effects of plasma treatment on cotton fabrics for a given set of parameters. By training six independent BRNN models, a reduction in model complexity and an enhancement in generalizability to unknown datasets were achieved. The input comprises plasma treatment parameters and color measurements of the cotton fabric before fading, while the output comprises color measurements after fading. The plasma treatment parameters included color depth, air (oxygen) concentration, water content and treatment time. Color measurements included CIE L*a*b*C*h and K/S values. Furthermore, 162 datasets derived from two-color mixed-dye cotton fabrics were utilized for training and testing. The outcomes revealed superior prediction performance of the BRNN compared to the Levenberg-Marquardt Neural Networks, with R2 values approaching 1 and 82.35% to 94.12% of the sample predictions lying within the acceptable color difference range. Through global sensitivity analysis, the impact of treatment parameters on fading effects was quantified, providing a scientific basis for parameter adjustment. This study not only elucidated the mechanism of plasma treatment-induced fading but also offers effective prediction tools for the intelligent and digital development of the fashion clothing fading domain.

Infection prevention and public health are a vital concern worldwide, especially during pandemics such as COVID-19 and seasonal influenza. Frequent manual disinfection and use of chemical spray coatings at public facilities are the typical measures taken to protect people from coronaviruses and other pathogens. However, limitations of human resources and coating durability, as well as the safety of disinfectants used are the major concerns in society during a pandemic. Non-leachable antimicrobial agent poly(hexamethylene biguanide) (PHMB) was mixed into photocurable liquid resins to produce novel and tailor-made covers for public facilities via digital light processing, which is a popular 3D printing technique for satisfactory printing resolution. Potent efficacies of the 3D-printed plastics were achieved in standard antibacterial assessments against S. aureus, E. coli and K. pneumoniae. A total of 99.9% of Human coronavirus 229E was killed after being in contact with the 3D-printed samples (containing the promising PHMB formulation) for two hours. In an eight-week field test in Hong Kong Wetland Park, antibacterial performances of the specially designed 3D-printed covers analysed by environmental swabbing were also found to be satisfactory. With these remarkable outcomes, antimicrobial products prepared by digital light processing 3D printing can be regarded as a reliable solution to long-term infection prevention and control.

Conventional scar treatment options of single pressure garment therapy (PGT) or silicone gel sheeting (SGS, Cica-Care®, Smith and Nephew, London, UK) alone lack mechanical property tunability. This article discusses a scar healing composite (PGF-Biopor®AB, Dreve Otoplastik GmbH, Unna, Germany) and how its mechanical properties can be tuned for improved mechanotherapy. A balance between compression and tension was achieved by tuning the tensile and shear properties, facilitating tension shielding and pressure redistribution for scar therapeutics. Biopor®AB-wrapping on biaxial-tensioned pressure garment fabric (PGF) allowed compression therapy and internal pressure redistribution. The Biopor®AB surface, with a coefficient of friction close to 1, strategically localizes stress for effective tension shielding. A substantial five-fold reduction in silicone tension, amounting to 1.060 N, achieves tension shielding and pressure redistribution. Simultaneously, a dynamic internal pressure-sharing mechanism distributes 0.222 kPa from each SPK-filament bundle, effectively managing internal pressure. Alongside the principle compression-silicone dual therapy, this composite design with dynamic internal pressure sharing and mechanical property tunability provides an additional pressure-relieving strategy for multiple scar therapeutics.

This study investigates the feasibility of using biodegradable secondary alcohol ethoxylate (SAE) non-ionic surfactant as a building block for the formation of reverse micelles, functioning as reactive dye carriers for the dyeing of cotton fabric in non-aqueous octane medium. Ten dyeing parameters were optimised, by a one-factor-at-a-time approach, namely: (i) effect of colour fixation agent; (ii) surfactant-to-water mole ratio; (iii) surfactant-to-co-surfactant mole ratio; (iv) volume of soda ash; (v) volume of dye; (vi) solvent-to-cotton ratio; (vii) dyeing temperature; (viii) dyeing time; (ix) fixation time; (x) soda-ash-to-cotton ratio. The colour properties, fastness properties and physical properties of SAE-dyed samples were experimentally compared with the conventional water-dyed samples. The optimised condition was found when SAE samples were dyed as follows: (a) 1:20 surfactant-to-water ratio; (b) 1:8 surfactant-to-co-surfactant ratio; (c) 10:1 solvent ratio; (d) 40 min dyeing time; (e) 60 min fixation time; and (f) 70 °C dyeing and fixation temperature. The results showed that SAE-dyed samples have better colour strength, lower reflectance percentage and comparable levelness, fastness and physical properties than that of water-dyed samples. SEM images revealed that the dyed cotton fibres had no severe surface damage caused by an SAE-based reverse micellar dyeing system. The TEM image depicts that the reverse micelle was of nanoscale, spherical-shaped and had a core–shell structure, validating the presence of reverse micelle as a reactive dye carrier and the potential of an SAE-based reverse micellar system for dyeing of cotton fabrics.

This work aims to examine the feasibility of using poly(ethylene glycol) (PEG)-based reverse micellar dyeing system for dyeing cotton fabric with the use of hot type trichloropyrimidine (TCP)-based reactive dyes and to evaluate the possibility of saving the dyeing energy used during the dyeing process. Experimental results show that fabrics dyed in reverse micellar system at 90°C can achieve higher color yield than the conventional water-based system at the same temperature. Further experiments using reverse micellar system for dyeing cotton at 80°C (a reduction of working temperature of 10°C) provided color yield comparable to that of conventional water-based system except the use of yellow dye. Both water-dyed and octane-dyed samples had good to excellent levelness, washing and rubbing fastness and 98.5% of octane could be recycled after distillation. Reflectance curves were identical in shape and the SEM images showed neither of the dyeing systems caused any significant damage to cotton fibers. These findings validated the possibility of using reverse micellar dyeing system for hot type TCP-based reactive dyeing of cotton fabrics at lower coloration temperature and energy consumption.

Reverse micellar dyeing of cotton woven fabrics with natural and biodegradable alkyl polyglucoside-based (APG-based) nonionic surfactant in decamethylcyclopentasiloxane (D5) non-aqueous medium with reactive dyes of different functional groups was investigated and compared with conventional aqueous water-based dyeing in terms of reflectance, color yield, levelness, CIE L*a*b* values, washing fastness and color fading properties. Experimental results have revealed that APG reverse micellar method can provide a higher color yield (K/Ssum value) and lower color reflectance (better dye uptake) than conventional water-based method, along with comparable washing fastness, leveling and color fading properties. Hetero-bifunctional reactive dyes can attain the highest color yield, followed by homo-bifunctional reactive dyes and mono-functional reactive dyes. Mono-functional reactive dyes and homo-bifunctional reactive dyes produce the best levelling properties with smallest levelness variation when compared with that of hetero-bifunctional reactive dyes in non-aqueous D5 dyeing medium.

Silicone gel sheeting (SGS) and pressure garment therapy (PGT) are the International Clinical Recommendations on Scar Management’s (ICRSM) two principal non-invasive scar-healing procedures. This study created a new PGT-SGS composite (PGF-Biopor®AB-based) via pre-strained screen printing. The Biopor®AB hydrophobicity and nylon-hydrophilicity enabled self-pumping for PGT-SGS dual therapy and pressure-driven “warp insertions” mobility facilitates active-fluid transportation. Integrating both therapies in a single PGT-SGS composite achieved efficacy optimization, and the 3D channel structure allowed trauma-free active-fluid transport. The 3D channel topology enables smooth diffusional transport in active-fluid transport environments—and active “nylon absorbency” improved water uptake and enhanced permeability capabilities with sustainability achieved dynamic hydration. The sole use of PGF-Biopor®AB composite in empirical trials verified dual therapy with trauma-free active-fluid transport with one-month efficacy, providing a new route for dual treatment and active scar management.

Healthcare workers in the hospital environment are at risk of infection and body fluids such as saliva, bacterial contamination, oral bacteria, etc. directly or indirectly exacerbate this issue. These bio-contaminants, when adhered to hospital linens and clothing, grow substantially, as conventional textile products provide a favorable medium for bacterial and viral growth, adding to the risk of transmitting infectious diseases in the hospital environment. Textiles with durable antimicrobial properties prevent microbial colonization on their surfaces and help contain the spread of pathogens. This longitudinal study aimed to investigate the antimicrobial performance of PHMB-treated healthcare uniforms during prolonged usage and repetitive laundry cycles in a hospital environment. The PHMB-treated healthcare uniforms displayed non-specific antimicrobial properties and remained efficient (>99% against S. aureus and K. pneumoniae) after use for 5 months. With the fact that no antimicrobial resistance was reported towards PHMB, the presented PHMB-treated uniform may reduce infection in hospital settings by minimizing the acquisition, retention, and transmission of infectious diseases on textile products.

The outbreak of COVID-19 has already generated a huge societal, economic and political losses worldwide. The present study aims to investigate the antiviral activity of Poly(hexamethylene biguanide) hydrochloride (PHMB) treated fabric against COVID-19 by using the surrogate Feline coronavirus. The antiviral analysis indicated that up to 94% of coronavirus was killed after contacting the CVC fabric treated with PHMB for 2 h, which suggests that PHMB treated fabric could be used for developing protective clothing and beddings with antiviral activity against coronavirus and can play a role in fighting the transmission of COVID-19 in the high-risk places.

The spread of COVID-19 has brought about huge losses around the world. This study aims to investigate the applicability of PHMB used for developing antiviral spandex clothing against coronavirus. PHMB was qualitatively determined on the surface of spandex fabrics by using BPB. The antiviral analysis shows that the PHMB-treated spandex fabric can kill 99% of the coronavirus within 2 h of contact, which suggests that the spandex fabric treated with PHMB could be used for developing antiviral clothing against coronaviruses for containing the transmission of COVID-19 in high-risk places. Furthermore, PHMB-treated spandex fabrics were shown excellent antibacterial activity against gram-positive S. aureus and gram-negative K. pneumoniae. The hand feel properties of Spandex fabric were not significantly affected by the PHMB coating in addition to the wrinkle recovery, which was obviously improved after PHMB coating.

In contrast to traditional pigment colors, structural colors have developed a great potential in practical applications, thanks to their unique nonfading and color tunable properties; especially amorphous photonic structures with noniridescent structural colors have attracted considerable attention and their applications have expanded to more fields. Herein, graphene oxide (GO) and reduced graphene oxide (RGO) enhanced noniridescent structural colors with excellent mechanical robustness were established by a time-saving approach named spray coating, which allows for rapid fabrication of angular independent structural colors by spraying different photonic spray paints (PSPs) to ensure color multiplicity that was adjusted by the silica nanoparticles (SiO2 NPs) sizes onto the substrates. The incorporation of poly(methyl methacrylate-butyl acrylate) (PMB) improved the adhesion existing among SiO2 inter-nanoparticles and between SiO2 NPs and the substrates, taking advantages of the low glass transition temperature (Tg) of butyl acrylate derivative polymer and made PMB embedded PSPs coated patterns being imparted with good mechanical robustness and abrasive resistance. The peculiar light adsorption of GO and RGO across visible light spectrum facilitate higher color saturation. The improvement in color saturation of GO and RGO doped PSPs is expected to boost the promising applications in structurally colored paintings, inks and other color-related optical fields.

Smart wearable textiles can sense, react, and adapt themselves to external conditions or stimuli, and they can be divided into active and passive smart wearable textiles, which can work with the human brain for cognition, reasoning, and activating capacity. Wearable technology is among the fastest growing parts of health, entertainment, and education. In the future, the development of wearable electronics will be focused on multifunctional, user-friendly, and user acceptance and comfort features and shall be based on advanced electronic textile systems.

Structural-coloured poly(styrene-methyl methacrylate-acrylic acid) (Poly(St-MMA-AA)) deposited carbon fabrics (Poly(St-MMA-AA)/PCFs) with fascinating colours (salmon, chartreuse, springgreen, skyblue, mediumpurple) changing with the (Poly(St-MMA-AA) nanoparticle sizes can be facilely fabricated by the thermal-assisted gravity sedimentation method that facilitates the self-assembly of Poly(St-MMA-AA) colloidal nanoparticles to generate photonic crystals. The particle sizes of Poly(St-MMA-AA) copolymer with core/shell structure varying from 308.3 nm to 213.1 nm were controlled by adjusting the amount of emulsifier during emulsion polymerisation. The presence of the intrinsic chemical information of Poly(St-MMA-AA) copolymer has been ascertained by Raman and Fourier Transform Infrared (FT-IR) Spectroscopy analysis. Colour variation of the as-prepared structural-coloured carbon fabrics (Poly(St-MMA-AA)/PCFs) before and after dipping treatment were captured while using an optical microscope. The structural colours of Poly(St-MMA-AA)/PCFs were assessed by calculating the diffraction bandgap according to Bragg’s and Snell’s laws. The Poly(St-MMA-AA) photonic crystal films altered the electrical properties of carbon fabrics with the resistivity growing by five orders of magnitude. The differential electrical resistivity between Poly(St-MMA-AA)/PCFs and wet Poly(St-MMA-AA)/PCFs combined with the corresponding tunable colours can be potentially applied in several promising areas, such as smart displays, especially signal warning displays for traffic safety.