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Fetal calf serum - (Dec/07/2010 )

Is it normal for fetal calf serum to be cloudy (precipitated) ?
Are they normaly more cloudy than FBS?

-Alvolo-

Hi!

FCS and FBS are the same.
Our experience is that if you store FCS at -20°C or -80°C and unfreeze it slowly you'll probably have precipitates. It's better to unfreeze it at room temperature and to invert it once in a while.

-Rumpel-

Rumpel on Tue Dec 7 15:46:49 2010 said:


Hi!

FCS and FBS are the same.
Our experience is that if you store FCS at -20°C or -80°C and unfreeze it slowly you'll probably have precipitates. It's better to unfreeze it at room temperature and to invert it once in a while.


thank you,but may i know what do you mean by unfreeze slowly?
water bath with 37 celcius consider slow or fast?

-Alvolo-

Alvolo on Sat Dec 11 14:45:19 2010 said:


Rumpel on Tue Dec 7 15:46:49 2010 said:


Hi!

FCS and FBS are the same.
Our experience is that if you store FCS at -20°C or -80°C and unfreeze it slowly you'll probably have precipitates. It's better to unfreeze it at room temperature and to invert it once in a while.


thank you,but may i know what do you mean by unfreeze slowly?
water bath with 37 celcius consider slow or fast?


37°C would be pretty fast, room temperature is fast enough, usually.

-Rumpel-

Rumpel on Sat Dec 11 20:45:53 2010 said:


Alvolo on Sat Dec 11 14:45:19 2010 said:


Rumpel on Tue Dec 7 15:46:49 2010 said:


Hi!

FCS and FBS are the same.
Our experience is that if you store FCS at -20°C or -80°C and unfreeze it slowly you'll probably have precipitates. It's better to unfreeze it at room temperature and to invert it once in a while.


thank you,but may i know what do you mean by unfreeze slowly?
water bath with 37 celcius consider slow or fast?


37°C would be pretty fast, room temperature is fast enough, usually.


It is frozen at -20C and I keep it at 4c(in refrigerator)overnight before using in next day.

-To dream to do-

In my old lab, we would put the frozen FBS in the same 37C water bath as the medium. Doesn't make a difference, really.

-lab rat-