The sequence of the first five N-terminal amino acids was determined and was found to be Gly-Asn-Cys-Trp-Leu.
The activity is determined by the ability to neutralize Activin A inhibitory effect of mouse MPC-11 cells. The expected ED50 is 100-400ng/ml corresponding to a Specific Activity of 2,500-10,000IU/mg in the presence of 7.5ng/ml Activin A.
Lyophilized from a concentrated (1mg/ml) solution containing no additives.
Sterile Filtered White lyophilized (freeze-dried) powder.
Greater than 95.0% as determined by:
(a) Analysis by RP-HPLC.
(b) Analysis by SDS-PAGE.
It is recommended to reconstitute the lyophilized Follistatin in sterile 18MΩ-cm H2O not less than 100ug/ml, which can then be further diluted to other aqueous solutions.
Lyophilized Follistatin although stable at room temperature for 3 weeks, should be stored desiccated below -18oC. Upon reconstitution FST should be stored at 4oC between 2-7 days and for future use below -18oC.
For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA).
Please prevent freeze-thaw cycles.
FST, FS, Activin-binding protein.
