Authors: D. Tessier, I. Radu and M. Filteau
Affilation: Center for Textile Technologies, Canada
Pages: 762 - 764
Keywords: antimicrobial coating, nanocrystal, biocidal, silver, wound dressing, bio-hazard
Antimicrobial fabrics find many technical applications in medical, hygiene, protection, sport, and industrial markets. However, antimicrobial fabrics differ in biocidal performance and durability. For example, such fabrics are used in wound dressings or bio-hazard protective clothings, and are nowadays compared in terms of "zone of inhibition" and "kill rate" of bacteria which are both related to the antibacterial activity. Metallic silver, silver oxides, and silver salts are known to have antimicrobial properties; unfortunately, slow-release systems, such as metallic silver, do not confer high zone of inhibition neither high kill rate because of limited availability of silver ions in such metallic systems. Therefore, it is highly desirable to obtain antimicrobial fabrics which possess high antibacterial activity while maintaining wide-range biocidal properties, such as those provided by slightly soluble silver salts. A colloidal solution of a silver salt was applied as a coating to different fabrics. Nano-sized crystals were deposited, as observed by electron microscopy, and presented a uniform surface distribution. The silver salt nanocrystals were obtained with the use of a suitable surfactant which prevented coagulation problems and large crystal precipitation. Moreover, the use of an antimicrobial surfactant improved the antimicrobial activity of the fabric, as demonstrated by antimicrobial test methods for antibacterial activity assessment. Using different, complementary antimicrobial compounds mixed together and applied as a coating, it resulted of a greater zone of inhibition evaluated with the parallel streak test method AATCC 147, while the biocidal fabric maintained a high level of performance after commercial washing or autoclaving.