Complementary techniques (spICP-MS, TEM, and HPLC-ICP-MS) reveal the degradation of 40 nm citrate-stabilized Au nanoparticles in rat liver after intraperitoneal injection

J Trace Elem Med Biol. 2019 Sep:55:1-5. doi: 10.1016/j.jtemb.2019.05.006. Epub 2019 May 10.

Abstract

Background: Due to the increased use of engineered nanoparticles (NPs), their tracing in environmental and biological systems is of utmost importance. Besides their accumulation within a biological specimen, little is known about their degradation and transformation into corresponding low-molecular species that might influence any toxicological impact.

Analytical methods: Wistar rats underwent intraperitoneal injections of 40 nm citrate-stabilized gold nanoparticles. Different liver samples were analysed for the occurrence of nanoparticles and potential degradation products by means of spICP-MS, TEM and HPLC-ICP-MS.

Main findings: Studies using spICP-MS revealed the presence of the originally administrated Au NPs (40 nm diameter) and some evidences of other Au-containing species due to the increased background signal. Images obtained by transmission electron microscopy (TEM) showed the predominant presence of particles of significantly smaller diameter (6 ± 2 nm). As complementary method, HPLC-ICP-MS confirmed the presence of both particle types indicating a degradation of the Au NPs accompanied by detection of low-molecular Au species.

Conclusions: This study underlines that degradation of gold nanoparticles to low-molecular gold species might have to be taken into account in future for studies on their toxicological behaviour and their potential use in clinical applications.

Keywords: Gold nanoparticles; HPLC-ICP-MS; Rat liver tissues; Single particle ICP-MS; TEM.

MeSH terms

  • Animals
  • Chromatography, High Pressure Liquid
  • Citric Acid / administration & dosage
  • Citric Acid / chemistry
  • Citric Acid / metabolism*
  • Gold / administration & dosage
  • Gold / chemistry
  • Gold / metabolism*
  • Injections, Intraperitoneal
  • Liver / drug effects
  • Liver / metabolism*
  • Mass Spectrometry
  • Metal Nanoparticles / administration & dosage
  • Metal Nanoparticles / chemistry*
  • Microscopy, Electron, Transmission
  • Particle Size
  • Rats
  • Rats, Wistar
  • Surface Properties

Substances

  • Citric Acid
  • Gold