ABSTRACT
OBJECTIVE: To establish a method for detecting the impurity components in human serum albumin by electrospray ionization mass spectrometry (ESI-Q-TOF MS) and investigate the impurity components in 28 batches of post-marketing albumin products from 27 companies. METHODS: According to Chinese Pharmacopoeia′s General Principles 4121, gel filtration column (Hiprep16/60 SepharylS-200HR) was used to separate the protein components. The dimer and multimer components were collected, then desalted, concentrated and digested by trypsin. The peptide was eluted by BEH C18(2.1 mm×100 mm,130) column with mobile phase consisting of water (0.1% formic acid)-acetonitrile in gradient elution mode. Chromatography-mass spectrometry was used to determine the secondary sequences of the peptides and the searching software (PLGS3.0) was used to identify the impurity protein components in albumin. RESULTS: A total of 23 impurity proteins were detected, among which apolipoprotein A-II, haptoglobin, and hempoexin, α-1B-glycoprotein and α-2-HS-glycoprotein were the impurity proteins common to all enterprise products; α-albumin (VE binding protein), N-acetyl-L-alanine amidase, haptoglobin-related proteins, hemoglobin (β subunit, α subunit), transthyretin and other proteins were found in the products of most companies. The number of heterologous proteins in each enterprise was between 8-17, and the numbers of impurity proteins in 27 companies were quite different. CONCLUSION: This method can be used for the investigation of unknown components in human serum albumin, which provides a guidance for the optimization of human albumin production process.