E3100 critical point dryer

E3100Critical point dryer

Critical point drying (sometimes referred to as supercritical drying, abbreviated asCPD）It's entering the scanning electron microscope（SEM）A traditional method of dehydrating and drying aquatic biological tissues prior to observation. The basic principle is that in a closed container, as the temperature increases, the evaporation rate accelerates, the gas phase density increases, and the liquid phase density decreases; When the temperature increases to a specific value, the density of the gas and liquid phases becomes equal, the interface disappears, and the surface tension becomes zero. The temperature and pressure at this point are called the critical point. The condition of zero surface stress can be used for drying biological samples to avoid damage, distortion, and false structural information caused by surface stress on the samples.

We often need to dehydrate biological samples, however, the critical point of water is+374℃ and3212 psiIt is very inconvenient to reach this critical point and it is easy to damage the sample. The most common and effective critical point drying medium isCO2Its critical point is at+31℃ and1072 psiBecauseCO2Not easily miscible with water, usually the sample needs to be dehydrated by ethanol gradient first, and then mixed with these two substances (ethanolCO2）Ethanol in the sample can be replaced by a miscible "medium" such as ethyl acetate or acetone. This is how to dry the medium (liquid)CO2）When converting from liquid to gas, the sample can be dried at the critical point without surface stress. The pre displacement treatment and final critical point drying process are as follows:

Wet water sample → gradient dehydration → ethanol wet sample → replacement with acetone wet sample → replacement with liquid stateCO2Wet sample → critical point drying → dry sample

E3100The large chamber critical point dryer is a device that exceeds35A classic standard instrument with a long history, used in many scanning electron microscopes around the world（SEM）Laboratory use.E3100Mainly used for critical point drying of biological and geological samples, it can also be used forMEMSControlled drying of MEMS, aerogel and hydrogel.

Instrument features:

•Proven reliability, globally installed6000Multiple unitsE3100Critical point dryer

•Durable, structurally simple, and easy to maintain, users can perform daily maintenance on their own

•Horizontal chamber and large observation window provide a very intuitive view of the liquid level and drying process

•Excellent security. This design has undergone independent type tests, proving that in the event of overpressure in the working chamber, the safety rupture disc is immediately released.

•Compatible with multiple sample processing, optional cover glass andTEMA sample holder with a porous leakage crucible is designed for fragile or very small samples.

E3100There is a large horizontal working chamber. The front of the chamber is equipped with a diameter of25The millimeter observation window provides unparalleled visibility of the liquid level line. The temperature of the working chamber increases through hot water circulation, and the heating method is hot water bath heating, which requires a matching hot water source. Circulating cooling water is also very useful, especially for continuous critical point drying processes/Or the instrument is located in a laboratory with high room temperature; You can use tap water for cooling, but a better method is to use optional heating/Cooling circulating water device, pre cool the chamber to below ambient temperature before loading the sample and liquid carbon dioxide, and later heat the chamber to the critical temperature.

oursCPDThe product line also includes those with vertical chambersK850Critical point dryer; Larger onesK850WMThe critical point dryer is designed for semiconductor applications and can perform critical point drying6Inch wafers. In addition, we also offer two freeze-drying machines: one using Peltier semiconductor refrigeration and the other using mechanical pumping for vacuum extractionK750X, as well as the use of liquid nitrogen refrigeration and turbo molecular pump vacuum extractionK775XThese dryer products are exclusively designed for scientific research purposes.