Fluorescence microscopy is very popular for imaging live cells. While it is used for a broad range of studies, it is often assumed that the imaging process itself is not harmful to cells.
Scientists explored this further and found there can be harm in looking. Be sure to read the article about this in the June 2013 issue of Cytometry Part A.
Standard fluorescent imaging of live cells is highly genotoxic (pages 552–560)
Jing Ge, David K. Wood, David M. Weingeist, Somsak Prasongtanakij, Panida Navasumrit, Mathuros Ruchirawat and Bevin P. Engelward
Article first published online: 6 MAY 2013 | DOI: 10.1002/cyto.a.22291
Link to article: http://onlinelibrary.wiley.com/doi/10.1002/cyto.a.22291/full
Using the “CometChip”, a novel DNA damage-measuring device, Ge and coworkers studied the impact of imaging on the cellular genome. Their results showed that direct light-induced damage is wavelength and time dependent. Even at wavelengths that do not induce pyrimidine dimers, the authors still observed DNA damage and showed that this damage was caused by oxidative DNA adducts. Additionally, there was an unexpected synergistic effect of light exposure in combination with the presence of fluorescent dye. Remarkably, a short exposure time can lead to damage levels equal to a highly toxic dose of radiation. Together, these findings delineate the relative severity of standard imaging procedures and highlight important considerations on imaging parameter selections.