Transmission Electron Microscopy: Applications in Biosafety Testing

This paper looks at the role Transmission Electron Microscopy (TEM) plays in biological sciences and in the assessment of biological safety, particularly in virology. The technique allows visualization of virus particles, particle size, morphology, and intra- and extra-cellular location, both in biological fluids and in vitro. TEM methods are used extensively for the identification and enumeration of virus particles in both diagnostic virology and biological safety.1-11 TEM is recommended in several guidelines, specifying which materials require testing including: cell lines, culture supernatants and fermenter bulk harvests. Although relatively insensitive, TEM is a ‘catch-all’ test for viral detection which other techniques, such as in vitro and in vivo assays, or ‘specific’ molecular assays, such as qPCR, may miss.