ABSTRACT
Cotton ber-based gauze has been used to dress wounds for hundreds of years because it is naturally soft, pliable, and absorbent. Cotton ber consists mainly of cellulose, which is a linear chain of several hundreds to over 9000 β (1→4)-linked d-glucose units. The hydroxyl groups of glucose in cellulose molecular can be partially or fully reacted with various reagents to afford derivatives with useful properties. Unfortunately, cotton ber is also an ideal place for settling and growing pathogenic bacteria because of its porous and hydrophilic structure. Therefore, antibacterial nishing is also of importance, especially in some specic applications like medical usage. There are many antibacterial agents used in this eld, including metal nanoparticles like silver and copper (Chen and Chiang 2008, Grace et al. 2009, Perelshtein et al. 2009, Chattopadhyay and Patel 2010, El-Rae et al. 2010, Ravindra et al. 2010, Hebeish et al. 2011, Xu et al. 2011). The antimicrobial activity of silver and copper nanoparticles is widely reported and is linked with ions that leach out from these nanoparticles. The activity is further enhanced due to their small size and high surface areato-volume ratio, which allows them to interact closely with microbial membranes. In fact, copper has been the most familiar antibacterial agent used for centuries. Bioactive copper nanomaterials are an emerging class of nano-antimicrobials providing complimentary effects and characteristics, as compared to other nano-sized metals, such as silver or zinc oxide nanoparticles (Daniela et al. 2012). Since the eighteenth century, copper had come into wide clinical use in the Western world, being for the treatment of mental disorders and afictions of the lungs. Early American pioneers moving West across the continent put silver and copper coins in large wooden water casks to provide them with safe drinking water for their long voyage. In the Second World War, Japanese soldiers put pieces of copper in their water bottles to help prevent dysentery. Copper sulfate is highly prized by some inhabitants of Africa and Asia for healing sores and skin diseases. NASA rst designed an ionization copper-silver sterilizing system for its Apollo ights. Today copper is used as a water purier, algaecide, fungicide, nematocide, and molluscicide, and as an antibacterial and antifouling agent (Cooney 1995, Stout et al. 1998, Cooney and Tang 1999, Fraser et al. 2001, Weber and Rutala 2001). Copper is considered safe to humans, as demonstrated by the widespread and prolonged use of copper intrauterine devices by women (Hubacher et al. 2001, Bilian 2002). In contrast to the low sensitivity of human tissue (skin or other) to copper (Hostynek and Maibach 2003), microorganisms are extremely susceptible to copper.
