Untitled - IAP/TU Wien - Technische Universität Wien

Nanostructure Characterisation by Electron Beam Techniques
Characterizing Nanoparticles for Environmental and Biological Applications
D. R. Baer, * M. H. Engelhard, P. Munusamy, S. Thevuthasan
EMSL Pacific Northwest National Laboratory, Richland, WA, USA
*don.baer@pnnl.gov
For the past decade we have been studying the behaviors of nanoparticles in environmental and
biological systems. This presentation will summarize some of the frequent characterization challenges
inherently associated with understanding nanomaterials in these environments and provide examples of how
surface and other characterization methods have helped us address some of the challenges. There is increasing
recognition that published reports on the properties and behaviors of nanomaterials have often involved
inadequate characterization [1]. Consequently, the value of the data in many reports is, at best, uncertain. It is
necessary for researchers to recognize the challenges associated with reproducible materials synthesis,
maintaining desired materials properties during handling and processing, and the dynamic nature of
nanomaterials at all stages of nanoparticle preparation, characterization and use [2]. Researchers also need to
understand how characterization approaches (surface and otherwise) can be used to minimize synthesis
surprises and to determine how (and how quickly) materials and properties change in different environments.
Some of the needs and lessons we have learned examining the ability of iron metal-core oxide-shell
nanoparticle to reduce environmental contaminants [3], observing the nature of ceria nanoparticles during
synthesis and aging [4] as well as how they interact with biological systems and measuring the stability of
silver nanoparticles in biological media will highlight both general analysis difficulties and the value of surface
sensitive analysis methods in combination with other techniques [5]. Because nanoparticles are often
synthesized, supplied or used in liquid media procedures to extract particles from the media maintaining as
much of the desired information as possible is important to enable analysis from surface sensitive methods
such as XPS to be valuable [3]. Equally important is the application of surface sensitive methods (such as
sum frequency generation) that can characterize particle surface in solution [2].
References
[1] R.M. Crist, J.H. Grossman, A.K. Patri, S.T. Stern, M.A. Dobrovolskaia, P.P. Adiseshaiah, J.D. Clogston,
S.E. McNeil, Integrative Biology 5 (2013) 66-73.
[2] D.R. Baer, et al., Journal of Vacuum Science & Technology A (2013) in press.
[3] J. T. Nurmi, V. Sarathy, P. T. Tratnyek, D. R. Baer, J. E. Amonette and A. Karkamkar, J. Nanopart. Res. 13
(5) 1937-1952 (2010).
[4] S. V. N. T. Kuchibhatla, A. S. Karakoti, D. R. Baer, S. Samudrala, M. H. Engelhard, J. E. Amonette, S.
Thevuthasan and S. Seal, J. Phys. Chem. C 116 (26), 14108-14114 (2012).
[5] D.R. Baer, D.J. Gaspar, P. Nachimuthu, S.D. Techane, D.G. Castner, Analytical and Bioanalytical
Chemistry 396 (2010) 983-1002.
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