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SLS Lab Basics 12 Place Microcentrifuge User Manual
11.2.2 Cleaning PC tubes
PC materials are low in chemical resistance against alkaline solutions. Avoid using neutral detergents
with pH higher than 9. Note that pH of some neutral detergents are still higher than 9 even if diluted
according to the instruction in the makers catalog. Use detergent with a pH between 7 and 9.
11.2.3 Autoclaving PA, PC and PP tubes
PA begins softening at about 120ºC, PC and PP at about 130ºC. Autoclave PA tubes at 115.0ºC (0.7kg/
cm
2
)
for 30 minutes and PC and PP tubes at 121ºC (0.1kg/cm
2
) for 20 minutes. If a certain temperature is
exceeded, the tubes may be deformed.
When using a sterilising chamber, please operate as follows:
(1) Place tubes in vertical position, mouths upward. If tubes are placed sideways, they may deform
into an oval shape due to gravity.
(2) Remove screw nuts and inner covers to prevent from deformation or rupture.
(3) Wait until the sterilising chamber cools down to the room temperature before the tubes are removed.
11.2.4 Condition and life expectancy of tubes
The life expectancy of plastic tubes depends on the characteristics of samples, speed of the rotor used,
and temperature applied and so on. When the plastic tubes are used for centrifuge of ordinary aqueous
samples (pH between 5 and 9), their life expectancies are defined as follows.
Operated at the maximum speed:
High quality tubes (PA, PC, PP): 30-50 operations
Ordinary tubes (PA, PC, PP): around 10 operations (Using in low speed can extend the tube life)
Life expectancy of tubes also depends on the pretreatment conditions such as cleaning and sterilisation,
lifetime can be cut down.
Notice: Do not use damaged or cracked tubes.
Formaldehyde
0
0
0
PA: Polyallomer PC: Polycarbonate PP: Polypropylene
