Electron microscopy (EM), although pivotal in life-science research, is limited in its capacity to work with live cells or at the length scales of whole complex tissues. Light microscopy techniques are often employed to image dynamic events in living cells and tissue and/or image complex tissues.
Each technology has its strengths and weaknesses and it is common to use both techniques to investigate cellular systems and events. This is normally undertaken as two separate studies and performed on different samples prepared specifically for light or electron microscopy. Using the same tissue allows an event observed by light microscopy to be directly linked to the higher resolution information provided by EM.
Thus, the capacity of EM is enhanced by correlative light and EM (CLEM) workflows where light microscopy events are co-localised with underlying ultrastructure.