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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 -20C or -80C 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 -20C or -80C 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 -20C or -80C 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?


37C 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 -20C or -80C 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?


37C 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-