The CLEM cryo-stage is a specialized stage designed for use on any upright or inverted light microscope for correlative cryo-light and cryo-electron microscopy (CLEM). It is specially designed grid holder allows up to nine 3 mm EM grids to be imaged via bright field and fluorescence light microscopy for determination of regions and/or cellular events of interest for later observation in the electron microscope. The grid holder is designed to keep the grids vitreous - well below the amorphous ice phase transition temperature - during transfer of grids into the grid holder and then into the cryo-stage. To eliminate frost build up on samples, the chamber can be gas purged and the grid holder has an integrated slide cover that is closed during transfer from liquid nitrogen into the cryo-stage chamber.
CLEM cryo-stage specification：
*Temperature Range： -190°C to 120°C liquid nitrogen cooling system is included）with temperature control program software
*Temperature Stability：±0.05°C at 100°C
*Minimum Heating and Cooling Rate：±0.1°C per hour
*Maximum Heating Rate：+60°C per minute at 100°C (CLEM upright); +80°C per minute at 100°C (CLEM inverted)
*Maximum Cooling Rate: -50°C per minute at 100°C
*Temperature Control Method: Switching PID
*Temperature Control Sensor: 100 Ω Platinum RTD
*Minimum Objective Working Distance: 5 mm
*Minimum Condenser Working Distance: 17.6 mm (CLEM upright),19.3mm(CLEM upright)
*Grid Holder: Holds nine 3 mm diameter sample grids. Grid holder remains chilled during transfers.
*Sample Viewing Aperture: 3 mm diameter
*X-Y Micropositioner: 10 μm resolution
*Swing cover: for easy sample access. Integrated slide cover on grid holder to eliminate moisture condensation on samples.
*Dual pane windows for better thermal isolation: removable and exchangeable windows. Integrated aperture window defrost system
*Gas purge sample chamber.
*Easy side sample loading with standard microscope slides
Advantages of CLEM cryo-stage：
*Cryo-LM maps of fluorescently labeled structures can be correlated to those mapped in the EM
*Light microscopy images give a valuable overview to place the context of the ultrastructural data obtained in the EM
*Samples remain vitreous after imaging in the cryo-LM
*Cryo-LM can be useful in determining ice thickness
*Cryo-LM is an invaluable tool for finding ROI in vitreous sections
*Visualizing plunge-frozen material before freeze substitution: finding transfected cells in a <100% transfected population or looking for cells in a particular stage/event
*Cryogenic temps reduce the photobleaching rate of GFP: possible application for super-resolution light microscopy