Fabrication of activated carbon fiber functionalized core–shell silver nanoparticles based in situ and low-cost technology for wound dressings with an enhanced antimicrobial activity and cell viability

Wound dressings are considered to be effective barriers against bacterial attack. They also facilitate wound healing in nursing-management functions. Silver nanoparticles (AgNPs) in wound dressings could overcome the problems associated with bacterial immunity, which is often observed in the use of conventional drugs. In the present work, a high concentration of cost effective and environmentally friendly AgNPs (16.3 ± 3.7 nm) with a uniform core–shell of poly(tannic acid) (PTA) was prepared. The preparation in high yield (95.8%) was based on an autoxidation-reduction reaction that was induced based on pH-responsive reduction affinity of tannic acid (TA). Despite the high antimicrobial activity of the prepared AgNPs@PTA, their cytotoxicity hindered their practical applications. The addition of different concentrations of natural cell viability enhancers, including TA and chitosan, to the prepared AgNPs@PTA solution improved significantly the cell viability. We have succeeded in improving the half maximal inhibitory concentration (IC₅₀) from 1 to 1000 ppm with minimal cytotoxicity toward L929 cells and 99.99% antimicrobial performance against both E. coli and S. aureus. Finally, the prepared AgNPs@PTA was integrated in an activated carbon fibers for wound-dressing application and exhibited excellent performance when compared with some commercial wound-dressing products.