Estimation of the Degree of Salivary Acidification of Recombinant-Human-Erythropoietin(rhEPO) / 中国药学杂志

ABSTRACT

OBJECTIVE: To detect and analyze the degree of salivary acidification of rhEPO isoforms. METHODS: The isoelectric points of rhEPO isoforms were determined with full column imaging capillary isoelectric focusing electrophoresis. And the charge distribution among rhEPO isoforms was analyzed. The degrees of rhEPO's total saliva acidification were measured using the method of appendices of Chinese Pharmacopoeia. At last, the degrees of saliva acidification of rhEPO isoforms were obtained using multivariate linear fitting. RESULTS: Nine kinds of rhEPO isoforms were distinguished and defined as isoform 1 to 9 with isoelectric points in the range of 3.6 to 5.1. There was one sialic acid molecule between two contiguous rhEPO isoform. Furthermore, the degrees of salivary acidification of the main four kinds of isoforms, 4-7, were 13, 12, 11 and 10 mol/mol, respectively. CONCLUSION:This study lays foundation for rhEPO biosimilar evaluation and further analysis of each isoform of rhEPO.