How do I store my FlexiTube siRNA Premix?

Reconstituted FlexiTube siRNA Premix can be stored at 4°C for one month.  For storage longer than one month, it is recommended to store the reconstituted mix at -20°C.  We found that after 5 freeze-thaw cycles, the potency of FlexiTube siRNA Premixes was not affected. However, although it is not recommended, we found that storage of reconstituted FlexiTube siRNA Premix for 6 months at 4°C did not reduce the gene silencing potency compared to reference transfections.