When function is biological: Discerning how silver nanoparticle structure dictates antimicrobial activity

Qingbo Zhang; Yue Hu; Caitlin M Masterson; Wonhee Jang; Zhen Xiao; Arash Bohloul; Daniel Garcia-Rojas; Hema L Puppala; George Bennett; Vicki L Colvin

doi:10.1016/j.isci.2022.104475

When function is biological: Discerning how silver nanoparticle structure dictates antimicrobial activity

iScience. 2022 May 30;25(7):104475. doi: 10.1016/j.isci.2022.104475. eCollection 2022 Jul 15.

Authors

Affiliations

¹ Department of Chemistry and School of Engineering, Brown University, Providence RI 02912, USA.
² Department of Chemistry, Rice University, Houston, TX 77005, USA.
³ Department of Biosciences, Rice University, Houston, TX 77005, USA.

Abstract

Silver nanomaterials have potent antibacterial properties that are the foundation for their wide commercial use as well as for concerns about their unintended environmental impact. The nanoparticles themselves are relatively biologically inert but they can undergo oxidative dissolution yielding toxic silver ions. A quantitative relationship between silver material structure and dissolution, and thus antimicrobial activity, has yet to be established. Here, this dissolution process and associated biological activity is characterized using uniform nanoparticles with variable dimension, shape, and surface chemistry. From this, a phenomenological model emerges that quantitatively relates material structure to both silver dissolution and microbial toxicity. Shape has the most profound influence on antibacterial activity, and surprisingly, surface coatings the least. These results illustrate how material structure may be optimized for antimicrobial properties and suggest strategies for minimizing silver nanoparticle effects on microbes.

Keywords: Microbiology; Nanomaterials; Nanoparticles; Nanotoxicology.