Page Y2: Cryo Workstation, UV/ Cryo Chamber, Cold Plates, Cryo-Gel™ & Cryogen Safety Gloves

RAPID IMMERSION FREEZER
Ultrarapid freezing, when used in conjunction with appropriate accessory processing methods, has long been recognised as providing preservation of ultrastructure, localisation of soluble inorganic and organic species, and preservation of antigenicity which is superior to that obtainable through conventional chemical fixation techniques and the use of cryoprotectants. Furthermore, it is the only procedure currently available for reproducibly capturing events that occur on a time scale of less than a few seconds.
Successful ultra-rapid freezing requires that heat be withdrawn so rapidly from an unfixed, un-cryoprotected sample that no ice crystal damage is visible at the electron microscopic level of analysis. This is not a trivial undertaking, and until recently, the improvements gained through ultrarapid freezing were often paid for in terms of decreased productivity. However, over the last several years, improvements in methodology and the introduction of refined equipment for the ultrarapid freezing of biological samples have significantly improved both the ease of application of the technique and the yield of well preserved samples. The EMS-002 Rapid Immersion Freezer allows for reliable, virtually routine freezing of biological samples.

Features:

Removable drop anvil assembly
Specimen holder
Stainless steel liquid nitrogen Dewar
Cryogen temperature controller
Drop release
Removable cryogen holder for safe disposal of cryogen
Frozen specimen work station

Process of Ultra-Rapid Sample Cooling
The EMS-002 achieves ultra-rapid cooling by quenching the sample in liquid propane or other suitable cryogen, cooled to near liquid nitrogen temperature, using a stainless steel vacuum insulated Dewar and a copper liquefaction chamber. Liquid nitrogen is poured into the Dewar to a level determined by the user. The initial cooling of the cryogen liquefaction chamber takes about fifteen to twenty minutes.
Gaseous propane is then admitted to the liquefaction chamber slowly enough to allow it to condense and fill the chamber with liquefied propane. The propane is allowed to cool to near liquid nitrogen temperature supervised by the digital temperature controller while a sample is being prepared for freezing. The device requires only about ten minutes to cool to operating temperature after the first filling of propane, and less than five minutes after subsequent fillings.
The operator can increase and decrease the rate of cooling by readjusting the level of liquid nitrogen in the Dewar. Heaters, built into the chamber walls and powered by a temperature controller, evenly warm the propane above its freezing point. The controller's temperature is set for the kind of cryogen being used, -185°C for use with commercial grade propane.
Chemically pure propane (map. 190°C) can also be used, but it is significantly more expensive than commercial grade propane and confers no particular advantage. Ethane and a non-flammable cryogen, SUVA-124 produced by Dupont, can also be used as a cryogen in this instrument. When using flammable cryogens like propane and ethane, we recommend using the EMS-002 in a fume hood.

Sample Preparation
The sample can be prepared using any favorite size EM grid if the system is being used for CryoTEM or Panama hat-shaped specimen carriers for freeze-fracture or freeze substitution. Once the sample is applied to the EM grid for instance, the excess must be carefully blotted away with a small piece of filter paper. The goal is to form a thin meniscus of specimen across the holes in the grid. Once achieved, insert the specimen holder in the “Drop Anvil” of the EMS-002.
For freeze fracture specimens, a thin spacer, typically an EM slot grid, is placed on the top of the sample hat, and a second hat is placed upside down on the sample and serves to prevent the sample from being crushed. If the specimen is large and sturdy enough that it can be supported at its periphery, a hole can be made in one or both hats to allow the propane to directly contact the specimen.

Results and Techniques
The technique provides higher rates of cooling than can be attained by plunging the sample into the cryogen by hand, because of the high velocity and accuracy of the sample entering the cryogen. Approximately 100 meters per second is the optimal plunging speed and provides more efficient heat exchange. The freezing is fast enough to capture rapid events and labile structures that are not seen in chemically fixed material. The technique has been applied to many types of specimens: aqueous suspensions and emulsions, tissue culture cells, suspensions of a wide variety of animal and plant cells and tissues. Specimens frozen with the EMS-002 may be freeze fractured (knife cut or double replica), freeze substituted, frozen thin sectioned or freeze dried. The samples may also be used for Cryo-SEM or TEM.

Temperature Controller
Allows the user to set desired hold temperatures of the cryogen being used. The easy to use controller also has an alarm which can be set to alert the user that the cryogen is warming up and the unit needs attention before the cryogen reaches evaporation temperature.

Recycling
The recycling time of the device is only a few minutes, just long enough to be ready again when processing of the last sample is finished. The device will operate for about two hours on ten litres of liquid nitrogen, including the initial cool down.

Applications:

Cryofixation of virus partials
Cryofixation of isolated or assembled macromolecules
Cryofixation of emulsions, paints and polymers
Cryofixation of suspensions and tissues for cryo-techniques like freeze fracture/etch, freeze drying, freeze substitution, CryoSEM and CryoTEM

Advantages:

Economical, universal application rapid freezing unit
Plunge freezing with temperature controlled cryogen
Frozen samples handled under cold dry nitrogen atmosphere
Rapid setup and easy use
Safe operation and easy cryogen disposal
Reproducible results
High and low set points for cryogen control

Specifications:
Dimensions: W279mm x D330mm x H356mm
Electrical: 100vac-240vac 50/60Hz 3a
Operational Temperature range: +30 to –200°C
Liquid Nitrogen Consumption: 1-2 litres per hour
Cryogen Volume: 20 mL

Optional Accessories: Ask for price
Climate Controlled Environmental Chamber
Inhibits air-drying and pre-cooling of sample prior to freezing. Allows easy sample blotting to achieve the optimal amount of sample on your grid.

Automatic Liquid Nitrogen Filling
Keeps a constant LN₂ level in the Dewar automatically.

Propane Transfer System

Cryo Transfer Face for SEM
Cryo Transfer Face for TEM

Metal Mirror Impact Freezing Fixtures
Allow a quick change from plunge freezing to impact freezing.

Diamond Anvil
Special freeze anvil with real diamond plate for better rapid freezing and easier specimen removal. Does not require polishing like standard copper anvils.

Freeze Forceps
Special self-locking tweezers specifically for use with the plunge freezer. Extra sets allow quicker turn around when freezing multiple samples.

Muscle Biopsy Clamps
Clamps designed for human muscle biopsies to keep the muscle from contracting during fixation. Now it is possible to improve the morphology of the sample through rapid freezing by plunging into liquid cryogen. Fits directly into the drop anvil on the plunge freezer.

The EMS-002 Plunge freezer comes with removable drop anvil assembly, stainless steel liquid nitrogen Dewar, cryogen temperature controller, cryogen holder and instructions. 110V-240V.

Y37000 EMS-002 Cryo workstation ask Availability