I have been noticing precipitates in my serum. Is this harmful to my cell culture and how can I reduced precipitates in my serum.

Answer

Finding precipitates in serum is not uncommon. They can be composed of proteins, lipids, salts and any combination of these.

It should not affect the performance of the serum at all. Precipitates can be minimized by careful thawing of the serum. Do not overexpose to heat and mix gently while thawing. Keep the number of freeze thaw cycles to a minimum.