This is a past event.

Biological Sciences Seminar Series

Dr. Erico Freitas

Research Scientist

Materials Science & Engineering

Michigan Technological University

Biography

Dr. Freitas worked for the multiuser electron microscopy facility at UFMG for 12+ years (2009-2021) with the day-to-day operation of the TEM and managed the TEM lab for 4 years (2017-2021). At Michigan Tech, he manages the FEI 200kV Titan Themis STEM in the Electron Optics Facility of ACMAL, the Applied Chemical and Morphological Analysis Laboratory.

Abstract

Transmission electron microscopy (TEM) is widely used for morphological studies of biological systems as it offers a much higher spatial resolution (over 200 times) than optical microscopy. Scanning transmission electron microscopy (STEM) provides even more possibilities for either imaging or chemical analysis, and its use in biological sciences has been growing over the last few decades.

Protein mass determination is one of the most widely used applications of biological STEM. Localization of ultrasmall bio-nanoparticles bearing heavy atoms is made possible by dark-field STEM imaging. The STEM imaging can also be combined with local chemical analysis by using either X-ray energy dispersion spectroscopy (EDS) and/or electron energy-loss spectroscopy (EELS). In either case, a STEM-EELS or STEM-EDS hyperspectral imaging makes up elemental mapping of subcellular structures.

All of these types of analysis and others are at hand at Michigan Technological University (MTU), which is home to a probe corrected FEI Titan Themis STEM, coupled with a super X EDS and GIF Quantum dual EELS. Not only ex-situ analysis but in-situ TEM/STEM is also possible to perform at the STEM Laboratory, such as liquid cell biological TEM/STEM where the specimens can be imaged within the liquid environment. During this seminar Dr. Freitas will present the capabilities of the STEM Laboratory at MTU and will address the types of ex-situ and in-situ analysis for biological systems.