With the emergence of Green Fluorescent Protein (GFP) in the 1990s the interest of live cell imaging studies has been tremendous. This, coupled with faster and more sensitive detection systems on microscopes provides even greater opportunities. Life science research has learned such an incredible amount from these live cell imaging studies that it is hard to imagine what research would be like without these tools.
The field of electron microscopy has not fully locked onto the momentum of the light microscopy wave, but in recent years it has become evident that the resolution of the light microscope is in some cases limiting in resolving the scientific question. Therefore, there has been increasing interest in developing techniques that combine the live cell imaging aspect of GFP with the high resolution of EM (Figure 1). GFP is not directly visible in the EM (electron microscopy) but can be visualised using antibodies or by photo conversion. However, such methods are based on samples that are chemically fixed at room temperature. It is well documented that this can introduce artefacts. Such artefacts are not visualised at the