FAQ1: Does the volume of T1 has to be exact?
A large volume is needed. It is important that the tip of the straw is moved when plunged in the medium and the dish is shaken at the same time. This to avoid decreasing temperature around the embryo (avoid recrystallization and aggregation of lethal ice crystals).
FAQ2: Precipitation is seen in VitriFreeze ESTM Freezing 2?
The precipitation is product specific and is due to the fact that when calcium is dissolved in PBS with 10% DMSO and 10% ethylene glycol, there is a probability that salt crystals are formed. Importantly, this does not affect the product performance and safety.