Merely Ag nanoparticles using different cellulose fibers as removable reductant

Merely silver nanoparticles (AgNPs) were synthesized as a colloidal solution without containing reducing or stabilizing agents using a totally green, one-pot, quite simple method. The unique advantage of this method is the use of a removable reducing agent to produce merely AgNPs. The reducing features and insolubility property of cellulose fibers make them the preferred potential removable reducing agents. Three different cellulosic fibers with different degrees of polymerization, namely viscose, lyocell and cotton fibers, were used. The best results for preparation of AgNPs was obtained by using viscose, followed by cotton then lastly lyocell fibers. When using viscose, the highest surface plasmon resonance peak for AgNPs and small particle size (mean = 9.5 nm) were obtained after 15 min. The carboxyl content of cellulose fibers was increased after treatment with AgNO₃, indicating the conversion of reducing groups of cellulose to carboxylic groups by the reduction of Ag⁺ to Ag⁰. Results showed that 30 % of AgNPs were aggregated and precipitated after storage for 2 months. The prepared AgNPs were more convenient to use in the medical and biomedical fields as the pure solution does not contain any other chemicals of reducing or stabilizing agents.