Rapid Kinetics of Size and pH-Dependent Dissolution and Aggregation of Silver Nanoparticles in Simulated Gastric Fluid.

Autor:	Axson JL; Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, Michigan 48109, United States., Stark DI; Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, Michigan 48109, United States., Bondy AL; Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States., Capracotta SS; Malvern Instruments, Westborough, Massachusetts 01581, United States., Maynard AD; Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, Michigan 48109, United States., Philbert MA; Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, Michigan 48109, United States., Bergin IL; Unit for Laboratory Animal Medicine, University of Michigan, Ann Arbor, Michigan 48109, United States., Ault AP; Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, Michigan 48109, United States; Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States.
Jazyk:	angličtina
Zdroj:	The journal of physical chemistry. C, Nanomaterials and interfaces [J Phys Chem C Nanomater Interfaces] 2015 Sep 03; Vol. 119 (35), pp. 20632-20641. Date of Electronic Publication: 2015 Jul 28.
DOI:	10.1021/acs.jpcc.5b03634
Abstrakt:	As silver nanoparticles (AgNPs) are used in a wide array of commercial products and can enter the human body through oral exposure, it is important to understand the fundamental physical and chemical processes leading to changes in nanoparticle size under the conditions of the gastrointestinal (GI) tract. Rapid AgNP growth was observed using nanoparticle tracking analysis with 30 s resolution over a period of 17 min in simulated gastric fluid (SGF) to explore rapid kinetics as a function of pH (SGF at pH 2, 3.5, 4.5 and 5), size (20 and 110 nm AgNPs), and nanoparticle coating (citrate and PVP). Growth was observed for 20 nm AgNP at each pH, decreasing in rate with increasing pH, with the kinetics shifting from second-order to first-order. The 110 nm AgNP showed growth at ≤3.5 pH, with no growth observed at higher pH. This behavior can be explained by the generation of Ag + in acidic environments, which precipitates with Cl - , leading to particle growth and facilitating particle aggregation by decreasing their electrostatic repulsion in solution. These results highlight the need to further understand the importance of initial size, physicochemical properties, and kinetics of AgNPs after ingestion to assess potential toxicity. Competing Interests: Notes The authors declare no competing financial interest.
Databáze:	MEDLINE
Externí odkaz:	Zobrazit plný text záznamu