A light-assisted in situ embedment of silver nanoparticles to prepare functionalized fabrics

This article presents a simple, one-step, in situ generation of silver nanoparticle-functionalized fabrics with antibacterial properties, circumventing the conventional, multistep, time-consuming methods. Silver nanoparticle formation was studied with a library of capping agents (branched polyethylenimine [BPEI] of molecular weight [M_w] 10,000 and 25,000, polyvinylpyrrolidone, polyethylene glycol, polyvinylalcohol and citrate) mixed with silver nitrate. The mixture was then exposed to an assortment of light wavelengths (ultraviolet, infrared and simulated solar light) for studying the light-assisted synthesis of nanoparticles. The formation of nanoparticles corresponded with the reducing capabilities of the polymers wherein BPEI gave the best response. Notably, the irradiation wavelengths had little effect on the formation of the nanoparticle when the total irradiation energy was kept constant. The feasibility of utilizing this method for in situ nanoparticle synthesis on textile fabrics (towel [100% cotton], gauze [100% cotton], rayon, felt [100% polyester] and microfiber [15% nylon, 85% polyester]) was verified by exposing the fabrics soaked in an aqueous solution of 1% (w/v) AgNO₃ and 1% (w/v) BPEI (M_w 25,000) to light. The formation of nanoparticles on fabrics and their retention after washing was verified using scanning electron microscopy and quantified by inductively coupled plasma optical emission spectrometry. The functional property of the fabric as an antibacterial surface was successfully demonstrated using model bacteria such as Staphylococcus aureus, Enterococcus faecalis and Escherichia coli. The successful generation of silver nanoparticle-functionalized textile fabrics without the use of caustic chemicals, solvents and excessive heating presents a major step towards realizing a scalable green chemistry for industrial generation of functionalized fabrics for a wide range of applications.