Fabrication of Highly Stable Polyurushiol-Decorated Silver Nanoparticles and Evaluation of Their Antibacterial and Anti-Microalgae Activities

The performance of silver nanoparticles (AgNPs) as highly efficient antimicrobial agents is limited by their agglomeration and instability. Environmentally friendly silver-based nanomaterials have attracted considerable attention, owing to the superior dispersion and antibacterial activity of AgNPs. In this work, polyurushiol (PUL) was used to modify an AgNPs-based material and prepare PUL-decorated AgNPs (PUL-AgNPs). The stability and dispersion of the composites varied with the reaction conditions. The PUL-AgNPs material showed higher antibacterial activity than the AgNPs, with minimum inhibitory concentration (MIC) values against E. coli and S. aureus of 3.13 mg/L ( p  < 0.01) and 6.25 mg/L ( p  < 0.01), respectively. PUL-AgNPs also showed inhibitory potential against three microalgae, P. tricornutum , I. zhanjiangensis , and N. closterium . The 72-h LC50 values of PUL-AgNPs for the three algae were 1.95, 1.89, and 4.07 mg/L, respectively. This study shows the promising potential of PUL-AgNPs for antibacterial and anti-microalgae applications, especially for marine antifouling. Graphical Abstract