HGH-20K quantitation was carried out by two independent methods1. UV spectroscopy at 280 nm using the absorbency value of 0.735 as the extinction coefficient for a 0.1% (1mg/ml) solution. This value is calculated by the PC GENE computer analysis program of protein sequences (IntelliGenetics). 2. Analysis by RP-HPLC, using a calibrated solution of GH-20K as a Reference Standard.

Lyophilized Pituitary Growth Hormone-20K although stable at room temperature for 3 weeks, should be stored desiccated below -18°C. Upon reconstitution and filter sterilization GH-20K can be stored at 4°C for up to 4 weeks. For long term storage and more diluted solutions it is recommended to add a carrier protein (0.1% HSA or BSA).Please prevent freeze-thaw cycles.