Growth hormone is a protein drug.  Since the activity of proteins cannot be determined routinely, changes in the spatial structure of proteins, especially mismatching of disulfide bonds, can affect the biological activity of proteins and thus affect the drug efficacy of proteins, and the specific activity can reflect this situation.  Specific activity refers to the biological activity unit per milligram of protein, which is an important index of recombinant protein drugs different from chemical drugs.  The detection of specific activity items can not only reflect the stability of the production process, but also compare the quality of the same product produced by different expression systems and different manufacturers.  The high specific activity indicates that the production technology of the product is more advanced, the purity is higher and the quality is better.  

As growth hormone agent iterative upgrade of new products, new second generation growth hormone agent does not contain preservatives, not only can solve the problem of injection of preservatives added, also avoids the phenol preservative use for a long time may bring the germ cell DNA damage and the central nervous and the potential risk of liver and kidney damage, is the best choice for clinical safe drug use.