Model 2552

Cryo Cartridge Specimen Holder
  • For specimens in autogrid cartridges that require liquid nitrogen cooling for transfer to a cryo transmission electron microscope (cryo-EM) for imaging
  • Base temperature less than -175 °C
  • Preserves the specimen’s vitreous state during transfer
  • Advanced mechanism for frost-free transfer
  • Integrated cradle clamp for tool-free specimen mounting
  • Resolution better than 0.20 nm
  • Low drift rate of 1.5 nm/min-1

Simple specimen loading and transfer

The innovative design of the specimen tip makes loading and unloading of the autogrid cartridges very easy. To load a specimen, the holder is inserted into the cryo workstation to cool down. The holder dewar and the cryo workstation are both filled with liquid nitrogen. 

The modular design of the cryo workstation allows you to reposition the reservoirs to enhance ease-of-use for both right- and left-handed operation.

Once a temperature of less than -175 °C is achieved, an autogrid cartridge  is loaded from the grid box into the holder tip. The holder accepts a 3.5 mm diameter autogrid cartridge, which is secured by the holder’s one-piece, integrated cradle clamp. The clamp automatically closes when the holder tip is retracted. Optionally, the cradle clamp can be closed with forceps or with the supplied specimen tool. The thin profile of the clamp maximizes specimen visibility, even at high-tilt angles. 

The specimen holder tip retracts inside an actively cooled cryo shield located within the holder. This shield prevents atmospheric water from condensing on the specimen during transfer to and from the microscope. The vitrified state of the specimen is maintained after transfer from the microscope to the workstation for subsequent imaging in cryo-TEMs with an autoloader.

Rapid cool down, extended hold time

The Cryo Cartridge Specimen Holder rapidly reaches a working temperature of less than -175 °C in either the cryo workstation or a TEM. Hold times in excess of 4 hours are readily obtained with the 200 ml dewar capacity. A zeolite absorption medium enhances dewar vacuum. The temperature controller connects directly to the specimen holder dewar and displays the holder tip temperature.

Regenerating the zeolite

The dewar zeolite must be regenerated periodically. This process is made easy with the one-touch Zeolite Regeneration button on the temperature controller. Fischione recommends the Model 9030 Turbo Pumping Station to evacuate the dewar during regeneration.