Protein content determination and specific activity analysis of recombinant human G-CSF final products

Objective: To determine and analyse the protein content of recombinant human G-CSF(rhG-CSF) final products,to evaluate the quality of rhG-CSF,to debate the possibility to add the protein content in the rhG-CSF final product requirement,and to debate the promotion of the national rhG-CSF criteria.Methods:Protein content of final products was determined by HPLC and the bioactivity was tested using NFS-60 cell proliferation/MTT method.The specific activities were the ratios of the bioactivity results to the protein content results.Results: The rhG-CSF samples were from 7 provinces in China.Their bioactivity was all in compliance with the requirement of the China Pharmacopeia Vol.Ⅲ(2005 edition),and the mean labeled relative bioactivity was 115.5%.Their protein contents range was 93%-137% of labeled,mean content was(118.5±13.6)%.Conclusion: The rhG-CSF final products are all in compliance with the requirements of the China Pharmacopeia Vol.Ⅲ(2005 edition).It shows that the rhG-CSF final products in China has generally high quality,but there is only one batch whose specific activity is a little lower than the bulk specific activity requirement of the China Pharmacopeia.So,it's necessary to add protein content test in the national rhG-CSF final product requirements.