Location: Cotton Quality and Innovation Research
2024 Annual Report
Objectives
1. Resolve modifications in cotton-based textiles to enable new commercial applications of skin and wound contacting materials.
2. Enable, through chemical technologies, commercial production of conventional cotton-based (barrier protective) materials.
3. Derive novel cotton value-added products through nanocellulosic materials and conventional processes.
Enhanced Cotton (EC) for Value Added Applications research proposed here is performed within the Cotton Chemistry Utilization Unit (CCU) and intends to enable cotton’s use in expanded high value applications. The objectives cover a broad range of potential product types and thus are divergent to some extent. However, we strive to overlap in shared collaborative direction as illustrated below. The research objectives proposed above, in conjunction with the Cotton Nonwovens research project, are targeted to improving U.S. cotton production by increasing the demand for domestic cotton. Increasing domestic consumption will come from identifying key consumer unmet needs specific for cotton, and areas where domestic cotton is required for end use products. Historically, solutions to downturns in U.S. cotton consumption have come from infusing cotton with new technologies that impart a competitive edge to cotton (e.g. permanent press) over synthetic fibers, or creating a customer-expedited supply of high quality cotton products that compete well with overseas production. However, in the current global market, development of proprietary technologies specific to the domestic consumption of cotton, are needed. Each of the research areas listed above is critically important at this time because each, if successful, will contribute greatly to increasing the domestic demands of cotton.
Approach
For Objective 1, a broad set of characteristics requires a varied approach to de novo design and preparation of cotton-based prototypes as body-contacting material. The target products of the approach are hemostatic, antimicrobial, chronic wound dressings and incontinence topsheet absorbents. Although each of these product areas share similar fabric characteristics they differ in functionality. Experiments for these four fabric groups will vary based on the functional target use. Evaluation of the influence of fiber structure on fabric surface polarity is important to hemostatic and incontinence fabrics, and design features at the cellulose crystallite level and molecular modifications are important to the chronic wound dressing. These will be assessed for activity through in vitro assessment models based on current leads, and prototypes developed from structure/function relations. Structure-activity relations of the fiber/fabric derivatizations will be examined at the fiber, microfibrillar and molecular level using fiber surface chemistry, electrokinetic, fluorescence, colorimetry, infrared spectroscopy, x-ray crystallography, and computational chemistry. The derivatized cotton materials will utilize chemical and physical cotton fabric modifications as are required to optimize activity and may employ some synthetic modifications i.e. protease sensor constructs are outlined in Obj. 3.
For Objective 2, discovery and development are outlined in three phases. In Phase 1, principle focus will be on the Layer-by-Layer (LbL) technology which will be applied to cotton nonwovens and compared on both bleached and greige cotton. Multifunctional activities will be explored i.e. antimicrobial, UV protection, and flame retardant activity. Phase 2 will predominantly be devoted to optimizing LbL functional properties to correspond with environmentally friendly, non-toxic approaches to conferring functionality i.e. antimicrobial, UV protection, and flame retardant activity while exploring ways to improve fabric hand. Phase 3 focus will be on working with stakeholders to identify LbL fabric technology with interest in applications i.e. military, sporting, wilderness medicine, fire barriers etc., and identifying key functionalities for cotton-based marketing and price point economy.
For Objective 3, mechanical milling of feedstock materials will yield a uniform-sized intermediate raw material, which will be subjected to alkaline and oxidative chemical treatments to remove pectin, hemicellulose and lignin. The ensuing suspension of nanocellulose will be hydrolyzed with dilute sulfuric acid and then subjected to high-pressure homogenization, leading to a sulfated cellulose nanofiber (sCNF). The sCNF products obtained by this process will be characterized by an array of analytical methods as detailed in the Methods section of (Jordan, Easson et al. 2019). From these isolated and characterized products, hydrogels, thin films and aerogels will be prepared and nanomaterial-treated cotton analogs will be prepared to obtain an initial nanomaterial-treated composites. Several lead compounds will be prepared to explore different chemistries.
Progress Report
Progress was made on all three objectives, all of which fall under National Program 306, Component 2, Quality and Utilization of Agricultural Products, Non-Food. Progress on this project focuses on Problem 2A to increase or protect the market demand for (or increase the value of) existing U.S.-produced non-food bio-based products derived from agricultural products and byproducts. Agricultural Research Service (ARS) researchers in New Orleans, Louisiana, have developed new products, applications, and processes for expansion of domestic cotton in the areas of: (1) moisture control properties and hygienic and cotton fabric hand applications; (2) in support of Agreement 6054-41430-009-003R and Material Transfer Agreement 18565 we converted textile scrap wastes to nanocellulose materials; (3) flame retardant cotton; (4) sensors that utilize a form of high surface area cellulose to detect disease biomarkers; (5) cotton-based blood clotting, and antibacterial fabrics for wound dressings; (6) established collaboration with ARS-Poplarville, Mississippi and transferred cellulose nanomaterials for a project to prevent white fly infestation and crop freeze protection; (7) established a collaboration with ARS-Fort Piece, Florida and transferred cellulose nanomaterials for a project to prevent citrus greening disease.
Treating battlefield injuries associated with blood loss and infection is a high priority U.S. military especially targeted to prolonged field care of seventy-two hours or more. In support of Objective 1, and in collaboration with the Defense Health Agency with Virginia Commonwealth University (VCU), we developed cotton-based nonwoven wound dressing prototypes designed to both promote blood clotting and prevent infection. Two animal models were developed by VCU to assess the hemorrhage control performance of the series of cotton dressings. The dressings contained compounds that worked synergistically with the cotton-based dressing material to initiate blood clotting and inhibit microbial growth. A small animal model for hemorrhage (spleen injury model) assessment was developed as a type of high-throughput assay to ‘screen’ up to 17 different gauze samples (including positive and negative controls). It was found that dressings treatments with ammonium zeolite performed similar, if not better than the battlefield standard for hemorrhage control at improving outcomes as measured by mean arterial pressure (MAP), heart rate, respiratory rate, temperature, and survival time. Based on these results four lead candidates were selected for testing in a modified swine femoral artery model designated by the Army Institute of Surgical Research as a hemorrhage control model. These were tested by the VCU collaborator. We determined blood clotting activity of the materials. Zeolite is a high surface area aluminosilicate that enhances blood clotting. It was found that ascorbic acid and zeolite-treated dressing composed of cotton performed as well as the standard dressing for care for hemorrhage control on the battlefield as judged in the swine femoral artery model.
Proteins known as growth factors play a significant role in the way wounds heal. Proteases are specialized proteins that can break down growth factors. Increased levels of proteases occur in a chronic wound and can prevent growth factors from functioning in wound healing. The incorporation of cotton cellulose nanofibers and hydrogen peroxide-generating cotton to dressings that remove excess levels of proteases from chronic wounds is being assessed as a route to promote wound healing. In support of Objectives 1 and 3, we designed a cellulose nanofiber tissue scaffold that was shown to promote growth of dermal fibroblasts. Since low levels of hydrogen peroxide tend to promote wound healing and stimulate growth factor production we tested cotton-based dressings for hydrogen peroxide levels which demonstrated comparable levels of hydrogen peroxide to commercial dressings used in chronic wounds. This research provides a starting point to develop multifunctional cotton-based dressing to promote wound healing.
There is a worldwide demand for effective, safe, and economical textile fabrics that prevent the spread of infectious diseases. Microbial growth on textiles poses the potential for contamination to the user especially when accessible medical care is inhibited. In support of Objectives 1 and 2 and in collaboration with the Defense Health Agency Agreement, we have developed antibacterial cotton fabrics consisting of vitamin C and silver treated fabrics that prevent the growth of bacteria and viruses at the 99.99 percent level. This year we showed efficacy of both the vitamin C and silver treated dressing against bacterial pathogens associated with a high level of virulence. The dressings were tested against six different pathogenic bacteria (E. aecium, S. aureus, K. pneumoniae, A. baumannii, P. aeruginosa. and E. cloacae) and found to be effective at the 99.99 percent level in all of them. We anticipated that the modified cotton fabrics will be applicable to a wide range of textile uses including facemasks, wound dressings, hygienic wipes, and fabrics used as barriers to the spread of microbes and viruses in hospitals.
Original approaches to prepare flame retardant cotton fabrics are required to advance the industrial efficiency of developing low-cost and effective flame retardant cotton. In support of Objective 2, we used microencapsulation and/or layer-by-layer technologies to modify cotton fabrics. The cotton fabrics designed contained environmentally friendly molecules including urea, diammonium phosphate, and phosphorous nitrogen rich containing compounds. We developed an efficient method for the chemical treatments of a series of fabrics. The fabrics tested positive for flame retardant activity. The treatment yields an effective flame retardant fabric, and places more chemical on the fabric (100 percent add-on). The compounds are also low-cost and commercially amenable to large-scale production of cotton fabrics.
In support of Objective 3, and Agreement 6054-41430-009-003R and Material Transfer Agreement 18565 with Cotton Incorporated, we were successful in the mechanical/chemical conversion of cotton denim apparel scrap wastes to cellulose nanomaterials. The conversion process involves the mechanical grinding of apparel scraps to a particle size suitable for further chemical modification to form the nanocellulose product. Experiments successfully converted denim apparel scrap wastes into cellulose nanocrystals and nanofibers. Additional experimentation successfully obtained optimal yields and further explored the possibility of obtaining additional value-added products from the cotton denim source material.
In support of Objective 3 further research was done to standardize the procedure for the XRD analysis of cellulose samples. Nanocellulose samples patterns were analyzed at the University of California Santa Barbara and The University of California Los Angeles to provide insight into the purity and structure of the samples. This approach more accurately determined the percentage of crystallinity in the cellulose.
In support of Objective 3 metallic nanoparticles were prepared within the intrafibrillar network of nanocellulose fibers. Patent Application Case No.0082.23 was filed on 03/28/2024 titled Self-Embedding Silver Nanoparticles Biomass Waste Compositions.
Accomplishments
1. Conversion of textile scraps to nanocellulose crystals and fibers. Apparel manufacturing contributes substantial amounts of textile scrap waste to landfills. Rather than regarding the apparel scraps as zero-value waste and disposing the unwanted apparel scraps in landfills, a more profitable solution is desired. Using mechanical and chemical means, ARS researchers in New Orleans, Louisiana, have successfully converted scrap clothing material from textile apparel manufacturing into cellulose nanofibers (CNFs) and cellulose nanocrystals (CNCs). These CNF and CNC materials have attracted a great deal of commercial interest as reinforcing agents in nanocomposites, polymers, gels, and emulsions due to their excellent tensile strength, sustainability and environmentally friendly properties. This wide-range of applications for CNFs and CNCs has increased their projected industrial demand at a combined annual growth rate of 19.7% from 2024 - 2029. This accomplishment provides a process by which two products of value are produced which have a broad range of applications from what would otherwise be discarded as waste material.
2. Cotton dressing for battlefield hemorrhage control. Excessive bleeding from traumatic wounds is the leading cause of death on the battlefield, and the second leading cause of death in the civilian trauma setting. One in five deaths worldwide has been attributed to sepsis which can often arise from infected wounds and pressure ulcers. Thus, materials that promote rapid blood clotting while preventing infection has relevance to both patient survival and optimal recovery. Cotton-based materials have been developed by ARS researchers in New Orleans, Louisiana, for application to hemorrhage control and prevention of sepsis. In a joint collaboration with the United States Marine Corp and Defense Health Agency. It was shown that a cotton-based dressing formulated with Vitamin C and zeolite improved survival from hemorrhage in the Army’s Institute of Surgical Research approved animal hemorrhage control model which was designed as part of a program to increase survival from battlefield trauma. The survival efficacy of animals treated with the dressing prototype using this approach was comparable to one now used currently on the battlefield as a standard for hemorrhage control. The dressing was also shown to be effective against the six pathogenic bacteria identified by the Armed Forces as being of chief concern. In addition, it fulfills requirements of a congressional mandate to use U.S. cotton in textiles products utilized by the Department of Defense. The potential impact of these types of cotton-based hemostatic dressings is to be found in improved trauma and infection treatment and prevention dressings used by the armed forces and first responders.
Review Publications
Easson, M.W., Jordan, J.H., Prevost, N.T., Edwards, J.V., Dupre, R.A., Hillyer, M.B., Lima, I.M., Nam, S. 2024. Assessment of Cellulose Nanofiber-Based Elastase Biosensors to Inflammatory Disease as a Function of Spacer Length and Fluorescence Response. ACS Applied Bio Materials. https://doi.org/10.1021/acsabm.3c00885.
Edwards, J.V., Prevost, N.T., Hinchliffe, D.J, Nam, S., Chang, S., Hron, R.J., Madison, C.A., Smith, J.N., Poffenberger, C.N., Taylor, M.M., Martin, E.J.,Dixon, K.J., 2023. Preparation and Activity of Hemostatic and Antibacterial Dressings with Greige Cotton/Zeolite Formularies Having Silver and Ascorbic Acid Finishes. International Journal of Molecular Sciences. https://doi.org/10.3390/ijms242317115.
Jordan, J.H., Gibb, C.L., Tran, T., Yao, W., Rose, A., Mague, J.T., Easson, M.W., Gibb, B.C. 2024. Anion Binding to Ammonium and Guanidinium Hosts: Implications for the Reverse Hofmeister Effects Induced by Lysine and Arginine Residues. Journal of Organic Chemistry. https://doi.org/10.1021/acs.joc.4c00242.