Amino acid-mediated loading of Ag NPs and tannic acid onto cotton fabrics: increased antibacterial activity and decreased cytotoxicity

Abstract In this paper, L-cysteine (Cys) is firstly bonded to the surface of cotton non-woven (CO) fabric as esterification. In this way, Ag+ and tannic acid (TA) are adsorbed onto the modified fabric via complexation and hydrogen bond interaction. After a sustainable one-step redox reaction, a Cys modified CO fabric decorated with Ag NPs and TA (CO-Cys-Ag-TA) is prepared. Because of the stabilizing effect of Cys and TA, the synthesized Ag NPs with a mean size of 88.9 nm are uniformly distributed on the modified fabric surface. Through the comparative test, it has been revealed that the antibacterial activity of Ag NPs is improved after loading TA, and the loading of Ag NPs significantly reduces the cytotoxicity of TA. In this context, the bacteriostatic reduction rate of CO-Cys-Ag-TA against S. aureus and E. coli is close to 100%, and its antibacterial activities are greater than 98.5% after 50 washing cycles. Meanwhile, its cell viability value reaches up to 88.0% with the presence of 0.1 mg/mL to 0.8 mg/mL CO-Cys-Ag-TA.