title: Aggregation factor analysis for protein formulation by a systematic approach using FTIR, SEC and design of experiments techniques.
abstract: A simple systematic approach using Fourier transform infrared (FTIR) spectroscopy, size exclusion chromatography (SEC) and design of experiments (DOE) techniques was applied to the analysis of aggregation factors for protein formulations in stress and accelerated testings. FTIR and SEC were used to evaluate protein conformational and storage stabilities, respectively. DOE was used to determine the suitable formulation and to analyze both the main effect of single factors and the interaction effect of combined factors on aggregation. Our results indicated that (i) analysis at a low protein concentration is not always applicable to high concentration formulations; (ii) an investigation of interaction effects of combined factors as well as main effects of single factors is effective for improving conformational stability of proteins; (iii) with the exception of pH, the results of stress testing with regard to aggregation factors would be available for suitable formulation instead of performing time-consuming accelerated testing; (iv) a suitable pH condition should not be determined in stress testing but in accelerated testing, because of inconsistent effects of pH on conformational and storage stabilities. In summary, we propose a three-step strategy, using FTIR, SEC and DOE techniques, to effectively analyze the aggregation factors and perform a rapid screening for suitable conditions of protein formulation.
authors.affiliation: National Institute of Advanced Industrial Science and Technology, Central 6, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan.
authors.forename: Yan Wen
authors.initials: YW
authors.lastname: Feng
authors.forename: Ayako
authors.initials: A
authors.lastname: Ooishi
authors.forename: Shinya
authors.initials: S
authors.lastname: Honda
mesh_terms: D002850:Chromatography, Gel / Q000379:methods*; D005163:Factor Analysis, Statistical; D006863:Hydrogen-Ion Concentration; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*; D013696:Temperature
chemical_list: D011506:Proteins