Tabletop Rotors and Tubes

Tubes and Accessories
kONICAL TUBES
konical tubes, used with conical adapters in swinging bucket rotors to
optimize pelleting separations, have a conical tip that concentrates the
pellet in the narrow end of the tube. The narrow bottom also reduces
the tube’s nominal volume and minimizes the amount of gradient
material needed when pelleting through a dense cushion. They are
available in polyallomer and Ultra-Clear. The konical tubes come
in both open-top and Quick-Seal tube designs. The Quick-Seal type
have bell-shaped tops to fit the floating spacers in the g-Max system
for smaller volume runs with faster pelleting.
TEMPERATURE LIMITS
Each labware material has a specified temperature range. Although
some ultracentrifuges can achieve temperatures as high as 45°C, only
certain tube or bottle materials can be run under these conditions.
Most containers are made of thermoplastic materials that soften at
elevated temperatures. This temperature-induced softening, together
with such factors as the centrifugal force, the run duration, the type of
rotor, previous run history, and the tube angle, can cause labware to
collapse. Therefore, if high-temperature runs—above 25°C—are
required, it is best to pretest labware under the actual experimental
conditions, using buffer or gradient of similar density rather than a
valuable sample.
• Plastic labware has been centrifuge tested for use at temperatures
between 2 and 25°C. For centrifugation at other temperatures,
pretest tubes under anticipated run conditions.
• If plastic containers are frozen before use, make sure that they are
thawed to at least 2°C prior to centrifugation.
Tabletop Ultracentrifuge Rotors and Tubes
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