Insight into Heterogeneous Distribution of Protein Aggregates at the Surface Layer Using Attenuated Total Reflection-Fourier Transform Infrared Spectroscopic Imaging
| Autor: | Hannah Tiernan, Bernadette Byrne, Sergei G. Kazarian |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Total internal reflection
Chemistry Infrared Surface Properties 010401 analytical chemistry Analytical chemistry Antibodies Monoclonal Protein aggregation 010402 general chemistry 01 natural sciences Spectral line 0104 chemical sciences Analytical Chemistry symbols.namesake Protein Aggregates Fourier transform Zinc Compounds Attenuated total reflection Spectroscopy Fourier Transform Infrared symbols Surface layer Particle Size Selenium Compounds Protein secondary structure |
| Zdroj: | Analytical chemistry. 92(7) |
| ISSN: | 1520-6882 |
| Popis: | Monoclonal antibodies (mAbs) have been used as therapeutics for the last few decades. It is necessary to investigate the stability of these mAbs under stress conditions and to elucidate aggregation mechanisms as a means of developing approaches which minimize the problem. Attenuated total reflection (ATR)-FTIR spectroscopic imaging allows probing of a sample at a depth of penetration of around 0.5-5 μm, which makes it suitable for the study of aggregated proteins when accumulated as a layer close to the surface of the ZnSe internal reflection element (IRE). Here, macro ATR-FTIR spectroscopic imaging, along with a variable angle of incidence accessory, have been used to differentiate between the secondary structure of proteins in bulk solution and those that have precipitated onto or near the ZnSe IRE surface. IgG spectra obtained from protein samples in individual wells have been averaged, extracted, and preprocessed, and the Amide I bands of the protein samples were compared and further analyzed to reveal protein distribution at the ZnSe IRE surface. These findings show depth profiling of IgG aggregates at the ZnSe IRE surface (0.5-5 μm) and do not follow a trend of decreasing protein presence with an increasing angle of incidence or increasing depth of penetration, suggesting an irregular distribution of aggregates in the z-direction. |
| Databáze: | OpenAIRE |
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