title: Evaluation of albumin structural modifications through cobalt-albumin binding (CAB) assay.
abstract: Human serum albumin (HSA) is the most abundant protein in the human body. HSA injections prepared by fractionating human blood have mainly covered the demand for albumin to treat hypoalbuminemia, the state of low concentration of albumin in blood. HSA in solution may exist in various forms such as monomers, oligomers, polymers, or as mixtures, and its conformational change and/or aggregation may occur easily. Considering these characteristics, there is a great chance of modification and polymer formation during the preparation processes of albumin products, especially injections. The albumin cobalt binding (ACB) test reported by Bar-Or et al. was originally designed to detect ischemia modified albumin (IMA), which contains the modified HSA N-terminal sequence by cleavage of the last two amino acids. In this study, we developed a cobalt albumin binding (CAB) assay to correct the flaws of the ACB test with improving the sensitivity and precision. The newly developed CAB assay easily detects albumin configuration alterations and may be able to be used in developing a quality control method for albumin and its pharmaceutical formulations including albumin injections.
authors.affiliation: College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Global Top5 Program, Ewha Womans University, Seoul 120-750, South Korea.
authors.forename: Eunyoung
authors.initials: E
authors.lastname: Lee
authors.affiliation: College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Global Top5 Program, Ewha Womans University, Seoul 120-750, South Korea.
authors.forename: Ji-Eun
authors.initials: JE
authors.lastname: Eom
authors.affiliation: College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Global Top5 Program, Ewha Womans University, Seoul 120-750, South Korea.
authors.forename: Kyung-Hwa
authors.initials: KH
authors.lastname: Jeon
authors.affiliation: Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, South Korea.
authors.forename: Tae Hee
authors.initials: TH
authors.lastname: Kim
authors.affiliation: Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, South Korea.
authors.forename: Eunnam
authors.initials: E
authors.lastname: Kim
authors.affiliation: Department of Chemistry and Nano Science, Ewha Womans University, Seoul 120-750, South Korea.
authors.forename: Gil-Ja
authors.initials: GJ
authors.lastname: Jhon
authors.affiliation: College of Pharmacy, Graduate School of Pharmaceutical Sciences, Ewha Global Top5 Program, Ewha Womans University, Seoul 120-750, South Korea. Electronic address: ykwon@ewha.ac.kr.
authors.forename: Youngjoo
authors.initials: Y
authors.lastname: Kwon
mesh_terms: D000418:Albumins / Q000737:chemistry*; D001681:Biological Assay / Q000379:methods*; D002626:Chemistry, Pharmaceutical / Q000379:methods; D003035:Cobalt / Q000737:chemistry*; D007267:Injections; D011485:Protein Binding; D012680:Sensitivity and Specificity
chemical_list: D000418:Albumins; D003035:Cobalt
keywords: 96-Well volume reaction; Albumin conformational change; Cobalt albumin binding (CAB) assay; Nitrogen monoxide