Controlled Release and Long-Term Antibacterial Activity of Dialdehyde Nanofibrillated Cellulose/Silver Nanoparticle Composites

Abstract

Nanofibrillated cellulose (NFC) is becoming popular in antibacterial material due to its favorable biocompatibility, stability, and modifiable properties, which give it a great potential as a template for the deposition of silver nanoparticles (Ag NPs). To investigate the deposition procedure and antibacterial ability of Ag NPs, dialdehyde nanofobrillated cellulose (DATNFC) prepared by oxidation of nanofibers was used to initiate the silver mirror reaction. Silver nanoparticles (∼31.07 nm) were successfully fabricated and uniformly anchored onto DATNFC (DATNFC@Ag). The film containing DATNFC@Ag via vacuum filtration showed excellent mechanical properties and exhibited efficient antibacterial activity against both Staphylococcus aureus and Escherichia coli. Dialdehyde nanofobrillated cellulose-induced silver ions release slowly, which displayed a controllable release of silver ions with a rate of 0.63% per 2 days and an ultralong Ag+ release period of 323.6 days. The Ag+ release time was prolonged due to the efficient in situ immobilization of silver nanoparticles. This study offers a novel and simple way to fabricate a green, controlled release and long-term antibacterial material based on dialdehyde nanofibrillated cellulose/silver-nanoparticle composites and opens a new window for the rapid and highly efficient synthesis of silver nanoparticles.