Intracellular uptake of magnetite nanoparticles: A focus on physico-chemical characterization and interpretation of in vitro data

Mater Sci Eng C Mater Biol Appl. 2017 Jan 1;70(Pt 1):161-168. doi: 10.1016/j.msec.2016.08.064. Epub 2016 Aug 28.

Abstract

Comprehensive characterization of nanoparticles associated with investigation of their cellular uptake creates the basis on which fundamental in vitro and in vivo studies can be built. In this work, a complex analysis of various surface-modified magnetite nanoparticles in biologically relevant environment is reported and the promotion of incorrect characterization into the results obtained from model biological experiments leading to false conclusions is demonstrated. Via a bottom-up approach from particle characterization by DLS towards interpretation of biological data based on cellular uptake, this work draws attention to the systematic propagation of errors stemming from inaccurate determination of input parameters for DLS, improper selection of particle size distribution, inadequate sampling, unknown colloidal behavior and the omission of fraction of particles complying with the internalization threshold. In addition, cellular uptake depending on the number of treated cells is shown. The definition of cellular uptake efficacy reflecting the size distribution of particles beside their absolute internalization is postulated.

Keywords: Cellular uptake efficacy; Dynamic light scattering; Internalization; Magnetite nanoparticles.

MeSH terms

  • A549 Cells
  • Chemical Phenomena*
  • Colloids / chemistry
  • Dynamic Light Scattering
  • Endocytosis
  • Humans
  • Hydrodynamics
  • Intracellular Space / metabolism*
  • Magnetite Nanoparticles / chemistry*
  • Magnetite Nanoparticles / ultrastructure
  • Particle Size
  • Solutions

Substances

  • Colloids
  • Magnetite Nanoparticles
  • Solutions