The E3100 large chamber critical point dryer has been an industry standard for over 35 years and is used in numerous scanning electron microscopy (SEM) laboratories around the world. Primarily used for critical drying of biological and geological specimens, the E3100 can also used for the controlled drying MEMs, aerogels and hydrogels.

The design of the E3100 features a large, horizontal pressure chamber measuring 63.5mm internal diameter x 82mm in length. The chamber has an external water jacket for temperature control and specimens are introduced via a removable rear door. The front of the chamber is fitted with a 25mm diameter window which gives an unsurpassed view of the liquid level during the critical point drying process.

Features:

• Proven reliability - over 6,000 critical point dryer installations world-wide.
• Simple robust construction - easy to maintain, many critical point dryer users carry out their own routine maintenance.
• Horizontal chamber and large viewing window - gives excellent visibility of the critical point drying process and of the fluid level in the chamber. Unlike many of the more complex critical point dryer designs it is much easier to see the phase change at the critical point.
• Large robust valves for ingress of CO2, draining of fluids and venting of gas. Very durable. The rapid ingress of CO2 helps prevent pre-drying of samples.
• Safety - every critical point dryer is independently pressure tested to 2500psi. A certificate is issued. A pressure bursting disc is fitted to safeguard against misuse.
• Sample handling - optional sample holders for coverslips and TEM grids.
• Porous pots are available separately for very small samples.

Valves and temperature control 

Dial gauges display pressure in the chamber and the temperature of water circulating through the external water jacket. Three pressure valves permit easy connection to a liquid CO2 cylinder and allow liquid agitation and venting of the chamber. 

A source of hot running water is essential. Cooling water is also useful, especially for sequential process runs. The temperature of the E3100 chamber is raised with a hot water supply. Mains (tap) water can be used but a more controlled method is by the use of the optional E3500 Thermocirculator, which is connected directly to the inlet and outlet of the water jacket. The temperature of the circulatory fluid can be pre-set (e.g. at 37?C, just above the critical temperature). Alternatively the optional E4860 Recirculating Heater/Chiller can be used to pre-cool the chamber to below ambient temperature prior to loading specimens and later in the process to heat the chamber to the critical temperature. 

Specimen holder (boat) 

This allows specimens in the intermediate fluid to be transferred into the critical point dryer. On sealing the chamber the intermediate fluid begins to drain and can be replaced with liquid CO2. In this way, specimens are never allowed to dry out during specimen loading and transfer. 

The E3100 is supplied with the E3100-01 specimen boat and has three slots each with three tissue baskets, making a total of nine. Specimens are loaded into each basket and the gauze lid is fitted to seal the tops. Other choices of holders are listed under Ordering Information. 

QUOE3100AE Large Chamber Critical Point Dryer

Chamber dimensions: 63.5 mm internal diameter x 82 mm length.

Supplied with:

E3100-01 specimen holder for tissue (boat), 1 m liquid CO₂ delivery tube, O-ring and L-gasket set (including window and door bonded seals), spare bursting disc and retaining copper washer, steel bar for tightening/untightening the door, flat wrench (for removing the window retaining ring) and a comprehensive operating manual.

Options and Accessories:

Specimen holders

QUOE3100-02 - Holder (boat) for microscope coverslips.

A specially adapted tissue holder (boat) allows glass coverslips to be held firmly during critical point drying and has a carrying capacity of 21 coverslips.

E3100-1 - TEM grid holder. For 3.05mm TEM grids (up to three).

CPD800A - Solvent-resistant porous pots (12.7mm x 15.5mm) with lids. Useful for critical point drying very small or very delicate specimens.

Spares

QUOE3100-061. Service kit for E3100 Critical Point Dyer (for use with ethyl alcohol).

Bonded chamber seals-Nitrile or EPDM?

The E3100 is fitted with a standard with nitrile bonded window and door seals. Nitrile is a good general material due to its ability to withstand attack by solvents such as ethanol. However, if acetone is used as the transition fluid then the EPDM seals have been found to be more resistant to chemical attack by that solvent.

If you are planning to use acetone as the transition fluid, please state this on the order and EPDM bonded seals will be fitted.

For existing instruments both Nitrile and EPDM bonded seal can be ordered as spares items.

QUOE3100-060. Seals set for E3100 (Nitrile).

QUOE3100-060/EPDM. Seals set for E3100 (EPDM).