Antimicrobial regenerated cellulose/nano-silver fiber without leaching

Abstract

The formation of antimicrobial regenerated cellulose fibers using an ionic liquid solvent, 1-butyl-3-methylimidazolium chloride, and silver nanoparticles was studied. The cellulose preparation and dispersion efficiency of the silver nanoparticles in the solvent were evaluated via scanning electron microscope and transmission electron microscopy in terms of different processing conditions. The influence of silver nanoparticles on regenerated cellulose fiber crystallization and strength was examined using a wide angle X-ray diffractometry and tensiometry, respectively. The bioactive efficacy of the cellulose/nano-silver fiber was tested in accordance with the standard method of ASTM E 2149-10. The cellulose/nano-silver fibers were bioactive and killed Escherichia coli almost completely without any leaching problems. The addition of nano-silver significantly increased the cellulose fiber tensile strength and modulus with an insignificant reduction in fiber elongation, and a slower thermal decomposition rate, evidenced by increased fiber crystallinity. Higher processing temperatures improved the nano-silver dispersion efficiency. The final nano-silver suspension in the regenerated cellulose matrix was composed of scattered clusters with an average size of 700 nm and a distribution density of 14,098 mm−2.

Cellulose Fibers for High-Performance Textiles Functionalized with Incorporated Gold and Silver Nanoparticles

“…The current state of the art mainly involves four technologies to combine cellulose and noble metal nanoparticles. Among them, electrostatic assembly (Dong & Hinestroza 2009;Yu et al 2018;Tang et al 2012), seed mediated synthesis followed by dip coating (Zheng et al 2013), insitu reduction (Tang et al 2014;Tang et al 2015a;Boufi et al 2011;Bumbudsanpharoke & Ko 2015;Cai et al 2009), and the incorporation of nanoparticles via dry-jet wet spinning (Chen et al 2015;Kulpinski 2007;Rac-Rumijowska et al 2017;Smiechowicz et al 2011;Smiechowicz et al 2018;Smiechowicz et al 2014;Wendler et al 2008).…”

“…In 2007, Wendler et al for the first time discussed the addition of silver nanoparticles to a Lyocell type spin dope to obtain antimicrobial regenerated fibers (Wendler et al 2007). This idea was also patented a year later (Wendler et al 2008), and has recently been transferred to cellulose ionic liquid systems (Chen et al 2015). Several other studies followed this approach indicating that silver nanoparticles could also be synthesized in-situ during the preparation of the spinning solution.…”

“…Afterwards, the solution is used to dissolve cellulose pulp under standard conditions, which is then dry-jet wet spun to man-made cellulose fibers (Kulpinski 2007;Smiechowicz et al 2011;Rac-Rumijowska et al 2017;Smiechowicz et al 2018;Smiechowicz et al 2014). As dissolution and regeneration entraps the nanoparticles in the fiber matrix, the metal cellulose composites are assumed to release less silver than any other methods described before (Chen et al 2015). Table 3 summarizes the cellulose and polyester based raw materials employed in this thesis according to a consecutive numbering.…”

“…The absorption of light depends on the particle size and shape, and can lead to a large spectrum of vivid colors (Eustis & El-Sayed 2006). Due to a restricted aspect ratio, spherical nanoparticles can only show colors from brown to yellow (Ag) (Chen et al 2015;Cai et al 2009;Smiechowicz et al 2011), or purple to orange (Jain et al 2006). Figure 27 depicts the absorbance spectra and color coordinates of Au, AgAu, and AgNP coated pulps and the regenerated fibers made thereof.…”

Skin wound healing with chitosan thin films containing supported silver nanospheres

“…For this efficient and highly controlled repair process to take place, numerous cell-signaling events are required, 30–32 and several combinations of polymers (as cellulose) plus AgNPs have been realized for incrementing the antimicrobial effects with promising results. 33…”