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Silk sericin (SS) was used as both a 3-dimensional matrix and reductant for the in situ synthesis of silver nanoparticles (AgNPs) finished on silk fabrics. We demonstrated enhanced UV protection and antibacterial properties using this synthesis which was an environmental friendly approach. Development and optimization was achieved using a central composite design (CCD) in conjunction with the response surface methodology (RSM). The goal was to identify the concentrations of SS and AgNO 3 that produced the optimal balance between UV protection and antibacterial activity, when tested against E. coli and S. aureus. The SS-AgNP bio-nanocomposites were characterized using Scanning Electron Microscope (SEM-EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR). Statistical analyses indicated an empirical second-order polynomial could accurately model the experimental values. To confirm that the optimal levels from RSM worked in practice, performance evaluations were conducted, including tests of cytotoxicity, of the durability and stability of UV protection, as well as of the antibacterial activity of the functionalized fabrics after repeated standard washing. The results suggest that these bio-nanocomposites have great potential for multi-functionalization on silk fabrics. Our method has been shown to convert the waste material (SS) to a fabric with high added value.

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This study investigated the enhancement of the ultraviolet (UV) protection and antibacterial properties of functionalized silk fabrics using a simple, inexpensive and environmental friendly approach. We demonstrated the in situ synthesis of copper nanoparticles (CuNPs) in a silk sericin (SS) matrix, using ascorbic acid as both a reducing agent and antioxidant. Development and optimization was achieved using a central composite design (CCD) in conjunction with the response surface methodology (RSM). The goal was to identify the concentrations of CuSO4 and SS that produced the optimal balance between UV protection and antibacterial activity, when tested against Escherichia coli and Staphylococcus aureus. The SS-CuNP bio-nanocomposites were characterized using scanning electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy. Statistical analyses indicated that an empirical second-order polynomial could accurately describe the UV protective factor, % reduction of S. aureus and % reduction of E. coli. The three-dimensional response surface graphs showed that the optimal concentrations of CuSO4 and SS were 2380 and 9500 ppm, respectively. To confirm that the levels identified using RSM were optimal in practice, performance evaluations were conducted. These investigated the durability and stability of UV protection and antibacterial activity after repeated washing cycles. The results suggest that these bio-nanocomposites have great potential for the multifunctionalization of silk fibers.

In recent years, the application of natural dyes in textile coloration has attracted significant study interest. In this current study, the bio-based dyeing of synthetic textile fiber, specifically acrylic yarn, with natural lac dye was investigated. The yarn was dyed using a meta-mordanting technique. The dyeing parameters, including temperature, time, pH of the dye bath, dye concentration, mordant type, and mordant concentration, were examined. Two eco-mordants, aluminium sulfate and ferrous sulfate, are compared against an eco-restricted copper sulfate in terms of color strength and fastness. The results demonstrated that the meta-mordanting technique can be used to dye acrylic fiber using natural lac dye. The optimum dyeing results were achieved using an acidic pH (2-3) and a temperature of 100℃ for 40 min of dyeing time. The color strength of the dyed samples was enhanced by the application of mordants. Color uniformity was achieved by controlling the temperature gradient in the Tg region. In terms of color change, the wash fastness properties of the dyed samples were found to be poor to moderate due to the dye's susceptibility to alkaline washing. In terms of color fastness to rubbing and light, ferrous sulfate and copper sulfate produced superior results.

Large quantities of discarded flowers from religious observances are left at temples and other places of worship, causing global disposal and environmental issues. Recycling and transforming such organic waste into value-added products is one of the most effective and beneficial solutions to the problem. The main goal of this study is to convert the most abundant temple wastes of marigold (Tagetes erecta) flowers into an eco-friendly dyestuff for the textile industry. Our study assessed the suitability of dye extract from garland waste for dyeing hemp fabric and valuated indicators including color strength (K/S) and fastness properties using tannic acid as a bio-mordant. Response surface methodology (RSM) was used for optimization of the dyeing process and evaluation of the interaction effects of various operating parameters. The optimal conditions were determined to be pH of 4.23, dyeing temperature of 99.98°C, and dyeing time of 82.64 min. To validate the optimal conditions identified by RSM, performance evaluations were conducted, including color fastness properties of the dyed hemp fabrics as well as the total color difference after repeated standard washing. These results demonstrate the use of aqueous extract from temple garland waste combined with bio-mordant represents a promising approach for textile dyeing.

Gold nanoparticles (AuNPs) were synthesized under ambient conditions from chloroauric acid in aqueous solution at pH 4. Tannin-rich extract from Xylocarpus granatum bark was used as both reducing and capping agent, rapidly converting Au (I) salt to AuNPs. Transmission electron microscopy showed the as-prepared AuNPs to be predominantly spherical, with an average diameter of 17 nm. The AuNPs were tested for catalytic reduction of Congo red (CR), a carcinogenic azo dye, in aqueous sodium borohydride solution. Cotton samples were coated with the AuNPs, taking on a reddish-purple color. The samples showed significantly reduced tearing strength after coating, though tensile strength was unaffected. UV-visible spectroscopy was used to determine the dye concentration in the water. CR degradation was observed only when AuNPs were present, and the efficiency of degradation was strongly linked to the AuNP loading. The AuNP-coated fabrics left only a 4.7% CR concentration in the solution after 24 h and therefore promise as a heterogeneous catalyst for degradation of CR in aqueous solution.