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Dressings for chronic human wounds have been aimed at protection, removal of exudate, and improved appearance. However since the time of ancient Greece wound care and dressing strategies have primarily relied on empiricism. Recent studies have shown that chronic wounds contain high levels of tissue and cytokine destroying proteases including collagenase and neutrophil elastase. Therefore we sought to develop an effective wound dressing that could absorb elastase through affinity sequestration. Cotton gauze was modified by oxidation, phosphorylation, and sulfonation to enhance elastase affinity by ionic or active site uptake. Type VII absorbent cotton gauze was oxidized to dialdehyde cotton which was subsequently converted in part to the bisulfite addition product. Gauze preparations were also phosphorylated and carboxymethylated. Modified cotton gauzes were compared with untreated gauze for reduction of elastase activity in buffered saline. Solutions of elastase that were soaked in oxidized, sulfonated, and phosphorylated cotton gauze showed reduced elastase activity. The initial velocities (v(o)) and turnover rates of elastase showed significant decreases compared with solutions taken from untreated gauze. The reduction in enzyme activity with dialdehyde cotton gauze was confirmed in solution by determining elastase inhibition with dialdehyde starch. The dialdehyde cotton gauze also decreased elastase activity in human wound fluid in a dose response relation based on weight of gauze per volume of wound fluid. Absorbency, pH, air permeability and strength properties of the modified gauze were also compared with untreated cotton gauze. This report shows the effect of reducing elastase activity in solution with cotton containing aldehydic or negatively charged cellulose fibers that may be applicable to treatment modalities in chronic wounds.

In order to delineate the effects on reagent migration on the textile-performance properties of durable-press fabrics, dimethyloldihydroxyethyleneurea (DMDHEU) and N-methylolpolyethyleneurea, degree of polymerization = 2, were applied to cotton printcloth under slow and rapid drying conditions, which effected uniform and nonuniform crosslink distributions through the fabric thickness. These reagents are representative of conventional and network polymer forming cross-linking reagents, respectively. The crosslink uniformity (or nonuniformity) was measured in the DMDHEU series with a negative Direct Red 81 staining technique. Fabrics with a uniform distribution of crosslinks throughout the fabric thickness were the point of reference. The concentration of crosslinks on fabric surfaces effected by reagent migration during rapid drying resulted in a) comparable development of resilience, b) slightly better retentions of breaking strength, tearing strength, and elongation, c) greater weight losses in Accelerotor abrasion, and d) comparable retention of Stoll-flex abrasion resistance. These trends occurred with both reagent systems and were detected at both the low and high levels of reagent incorporation. The results are discussed in relation to the distribution of crosslinks.

SynopsisTo characterize the pore structures of purified cotton, NaOH-treated cotton, and liquid-NH,-treated cotton, we have (1) investigated the feasibility of preparing useful chromatographic columns from whole cotton fibers and (2) studied the elution behavior (penetration) of three selected classes of water-soluble solutes from columns of the three types of cotton fibers. The solutes were series of common oligomeric sugars, oxyethylene glycols, and oxyethylene glycol dimethyl ethers having molecular weights or dimensions in the range of conventional dyes and finishing agents. Substantial differences in dyeing performance and in resilience have been reported for the cottons under study. Differences in performance qualities of these fibers in fabric form are explained in terms of the substantial differences in sizes and abundance of pores in the fibers.

This article covers nomenclature, sources, preparation, uses, microcrystalline cellulose, structural chemistry, reactions, solvents, and liquid crystals. Cellulose for commercial purposes comes mostly from wood and cotton, whereas cellulose for research comes from bacteria, algae, and ramie (also a textile fiber). Preparation includes pulping and purification, with an alternative method of steam explosion. The pore structure of cellulose is mentioned, along with the buildup of cellulose molecules into entire fibers. Emphasis is given to cellulose crystal structure. Recent research has provided structures with much better resolution for two crystal forms. Most native cellulose is a mixture of two crystalline phases. Cellulose solutions are important to the rayon and cellophane industries, and new solvents are of interest because they may lessen pollution and might permit commercial production of stronger cellulosic materials through the formation of liquid crystals. Figures include the chemical and physical structures of the molecule, including in solution, X‐ray diffraction patterns, the structure of a microfibril, and the unit cell structures of cellulose I–IV.

The balance of textile performance properties and the distribution of crosslinking reagent residues throughout fabric were studied in relation to lick roller application of DMDHEU. Features of the lick roller treated fabric were compared to the conventional pad(immersion)-dry-cure product and to a corresponding product designed to have a high degree of uniformity of reagent residue distribution throughout the thickness of the fabric by minimizing migration. A special Osnaburg-fabric was used to facilitate several aspects of the study including the measurement of distribution of reagent residues. The fabric treated to a high degree of uniformity of reagent residue distribution exhibited substantially higher abrasion resistance than the conventional product when compared at equal levels of durable press appearance rating; it was slightly lower in strength properties. The product from lick roller treatment at optimum liquor pickup approached the high uniformity standard in uniformity of reagent residue distribution throughout the fabric thickness and in abrasion resistance. In breaking strength, tearing strength, and elongation (especially in the warp), this product from lick roller treatment performed close to the high uniformity standard. The performance of another product from lick roller treatment that involved lower liquor pickup is also described, Performance properties and distributions of reagent residues are discussed in detail.

The absorption spectra of several phenyl-substituted oxiranes in 3-methylpentane at -196°are highly structured and characterized by a 0-0 band at 271 ± 3 nm with a more intense, structureless band at ~230 nm.The fluorescence emission of these compounds occurs at 285-340 nm, with a maximum at 305-310 nm. The isomeric 2,3-bis-a-naphthyloxiranes and tetraphenylepisulflde have also been studied. Irradiation into the 0-0 or higher energy absorption bands causes formation of a colored intermediate. Subsequently, the parent alkene and arylcarbene(s), and carbonyl compound(s) are formed in a manner dependent on oxirane symmetry. Phenyloxirane behaves atypically and no divalent carbon fragments are formed. A consistent mechanistic pathway is proposed to explain the photochemistry and spectroscopy of the oxiranes and their photoproducts. Several aspects of the spectroscopy and photochemistry of phenyloxiranes have been studied.2 Griffin and coworkers3 have found that arylcarbenes are genii) (a) Taken from the thesis submitted by R. O. B. in partial fulfillment of the Ph.D. requirements

Utilization of highly speci®c enzymes for various textile-processing applications is becoming increasingly popular because of their ability to replace harsh organic/inorganic chemicals currently used by the textile industry. Thus, a signi®cant decrease in the amount and toxicity of textile wastewater ef¯uents is achievable. It was established that ultrasound does not inactivate the complex structures of enzyme molecules and as a consequence there was signi®cant improvement in the performance of both cellulase and pectinase enzymes. The experimental data indicate that the maximum bene®t provided by sonication occurs at relatively low enzyme concentrations. Ultrasonic energy signi®cantly intensi®ed enzymatic activity on various types of cotton fabrics, but it did not contribute to a decrease in tensile strength. The combined enzyme/sonication treatment of cellulosic textiles offers signi®cant advantages such as less consumption of expensive enzymes, shorter processing time, less ®ber damage and better uniformity of treatment. Published in