Carboxymethyl cotton and calcium alginates have ion exchange properties. The paper discussesa cation-exchange-based development of silver antimicrobial nonwovens from sodium salt ofcarboxymethylated cotton, and commercially available calcium alginate dressings that should beeffective for burn wounds. We have prepared carboxymethylated cotton nonwovens by treating cottonnonwovens with caustic soda and monochloroacetic acid in 80/20 to 90/10 ethanol/water medium.Ethanol preserved the fibrous form of nonwovens, imparting the desired properties of improvedmoisture retention, high bound water, and high swellability. The presence of a functional group, methylcarboxyl (-CH2COONa) in carboxymethyl nonwovens enabled us to carry out further chemicalmodification to develop antimicrobial products. Antimicrobial nonwovens were prepared with silvernitrate and carboxymethylated cotton in a two-step reaction in an ethanol/water solution. Similarly, wealso prepared antimicrobial calcium/sodium alginate nonwovens by treating alginates with silver nitratein ethanol/water. By imparting antimicrobial properties to alginates that are used as moist wounddressings, we have expanded the functionality of the dressings. From the behavior of antimicrobialrelease and the suppression of bacterial proliferation, it was apparent that the dressings containing thesilver antimicrobial agent would protect the wound surfaces from microbial invasion and effectivelysuppress bacterial proliferation. The antimicrobial activity of these products along with their untreatedcontrols were evaluated as effective against both gram positive (Staphylococcous aureus) and gramnegative microbes (Klebsiella pneuoniae) by North American Science Associates (NAMSA).
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