IN VITRO TRANSMISSION ELECTRON MICROSCOPY OF NANOPARTICLES

 

Kate L. Klein, Ian M. Anderson

 

Surface and Microanalysis Science Division,

Chemical Science and Technology Laboratory, NIST

 

 

With the burgeoning application of nanomaterials, there are rising concerns over the still undetermined toxicity and fate of engineered nanoparticles upon their release into our bodies and our surroundings.  Toxicology studies in the literature, for the most part, consist of highly conflicting, incomparable results due to many uncertainties in the critical material properties.  There is at present no technique that combines the ability to characterize functionalized nanostructures in their relevant aqueous (in vitro) environment with the high spatial resolution necessary to image individual nanostructures.  The development of such a technique would provide unique and pertinent data about the behavior of functionalized nanostructures and would open the door to dynamic studies that could not otherwise be addressed.

This research seeks to establish methods for the characterization of nanoparticles in solution by conventional Transmission Electron Microscopy (TEM) using a customized liquid flow cell specimen holder.  This poster will present an overview of the approach as well as preliminary results toward optimizing the 300 kV TEM imaging of a NIST Standard Reference Material: 10-nm-diameter Au nanoparticles suspended in aqueous solution.  The fundamental aspects of electron interactions with the sample media, such as inelastic scattering and plasmon losses, will be discussed.  The development of this in vitro technique will enable the characterization of functional nanostructure systems to address more complex problems in future studies.