Self-induced transformation of raw cotton to a nanostructured primary cell wall for a renewable antimicrobial surface

Soil Biodegradation Resistance of Cotton Fiber Doped with Interior and Exterior Silver Nanoparticles

Engineering fibers with nanomaterials is an effective way to modify their properties and responses to external stimuli. In this study, we doped cotton fibers with silver nanoparticles, both on the surface (126 ± 17 nm) and throughout the fiber cross section (18 ± 4 nm), and examined the resistance to soil biodegradation. A reagent-free one-pot treatment of a raw cotton fabric, where noncellulosic constituents of the raw cotton fiber and starch sizing served as reducing agents, produced silver nanoparticles with a total concentration of 11 g/kg. In a soil burial study spanning 16 weeks, untreated cotton underwent a sequential degradation process-fibrillation, fractionation, and merging-corresponding to the length of the soil burial period, whereas treated cotton did not exhibit significant degradation. The remarkable biodegradation resistance of the treated cotton was attributed to the antimicrobial properties of silver nanoparticles, as demonstrated through a test involving the soil-borne fungus Aspergillus flavus. The nonlinear loss behavior of silver from the treated cotton suggests that nanoparticle depletion in the soil depends on their location, with interior nanoparticles proving durable against environmental exposure.

Preparation and Activity of Hemostatic and Antibacterial Dressings with Greige Cotton/Zeolite Formularies Having Silver and Ascorbic Acid Finishes

The need for prehospital hemostatic dressings that exert an antibacterial effect is of interest for prolonged field care. Here, we consider a series of antibacterial and zeolite formulary treatment approaches applied to a cotton-based dressing. The design of the fabric formulations was based on the hemostatic dressing TACGauze with zeolite Y incorporated as a procoagulant with calcium and pectin to facilitate fiber adherence utilizing silver nanoparticles, and cellulose-crosslinked ascorbic acid to confer antibacterial activity. Infra-red spectra were employed to characterize the chemical modifications on the dressings. Contact angle measurements were employed to document the surface hydrophobicity of the cotton fabric which plays a role in the contact activation of the coagulation cascade. Ammonium Y zeolite-treated dressings initiated fibrin equal to the accepted standard hemorrhage control dressing and showed similar improvement with antibacterial finishes. The antibacterial activity of cotton-based technology utilizing both citrate-linked ascorbate-cellulose conjugate analogs and silver nanoparticle-embedded cotton fibers was observed against Staphylococcus aureus and Klebsiella pneumoniae at a level of 99.99 percent in the AATCC 100 assay. The hydrogen peroxide levels of the ascorbic acid-based fabrics, measured over a time period from zero up to forty-eight hours, were in line with the antibacterial activities.

Unveiling the Hidden Value of Cotton Gin Waste: Natural Synthesis and Hosting of Silver Nanoparticles

Cotton gin waste presents a significant challenge in the cotton ginning industry due to its abundant generation and limited disposal options. In this study, we explored the potential of cotton gin waste as a naturally occurring source material that can synthesize and host silver nanoparticles. The noncellulosic constituents of cotton gin waste served as effective reducing agents, facilitating the conversion of silver ions into silver atoms, while its porous structure acted as a microreactor, enabling controlled particle growth. A simple heat treatment of cotton gin waste powder in an aqueous silver precursor solution actualized the in situ synthesis of silver nanoparticles, without the need for additional chemical agents. Remarkably, a high concentration of silver nanoparticles (14.7%) with an average diameter of approximately 27 nm was produced throughout the entire volume of cotton gin waste. Electron microscopic images of cross-sectioned cotton gin waste confirm the internal formation of nanoparticles. Rietveld refinement analysis of X-ray diffraction patterns showed that the majority of the nanoparticles possess a cubic silver crystal structure. By leveraging the well-known biocidal properties of silver nanoparticles, the resulting silver nanoparticle-filled cotton gin waste holds promise for novel antimicrobial and antifungal material applications.

Washable Antimicrobial Wipes Fabricated from a Blend of Nanocomposite Raw Cotton Fiber

In this study, a simple and effective way to produce washable antimicrobial wipes was developed based on the unique ability of raw cotton fiber to produce silver nanoparticles. A nanocomposite substructure of silver nanoparticles (25 ± 3 nm) was generated in raw cotton fiber without reducing and stabilizing agents. This nanocomposite raw cotton fiber (2100 ± 58 mg/kg in the concentration of silver) was blended in the fabrication of nonwoven wipes. Blending small amounts in the wipes-0.5% for antimicrobial properties and 1% for wipe efficacy-reduced the viability of S. aureus and P. aeruginosa by 99.9%. The wipes, fabricated from a blend of 2% nanocomposite raw cotton fiber, maintained their antibacterial activities after 30 simulated laundering cycles. The washed wipes exhibited bacterial reductions greater than 98% for both Gram-positive and Gram-negative bacteria.