Label-free detection of protein-protein interactions at the GaAs/water interface through surface infrared spectroscopy : discrimination between specific and nonspecific interactions by using secondary structure analysis
Here, we propose a label-free detection of protein-protein interactions that enables simultaneous qualitative analysis of target proteins by using Fourier transform infrared (FTIR) absorption spectroscopy in multiple internal reflection geometry (MIR-FTIR). Using this method, the target proteins wer...
| Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 23(2007), 24 vom: 20. Nov., Seite 12287-92 |
|---|---|
| 1. Verfasser: | |
| Weitere Verfasser: | , , , , , |
| Format: | Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2007
|
| Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Arsenicals Peptides Proteins Water 059QF0KO0R gallium arsenide 27FC46GA44 Gallium |
| Zusammenfassung: | Here, we propose a label-free detection of protein-protein interactions that enables simultaneous qualitative analysis of target proteins by using Fourier transform infrared (FTIR) absorption spectroscopy in multiple internal reflection geometry (MIR-FTIR). Using this method, the target proteins were detected based on the peak height of the amide I and amide II bands, while discrimination of specific and nonspecific signals is made based on the secondary structure of the analytes, which is determined through second-derivative analysis of the amide I band. As a model system, an antigen peptide was immobilized on the surface of GaAs, which was transparent to mid-infrared light, and the interaction with its antibody was examined in aqueous media. We demonstrated that the binding of the antibody to the antigen immobilized on a GaAs surface selectively gave rise to beta-sheet amide I vibrations (1639 and 1690 cm-1), while no structurally related signals were induced by nonspecifically adsorbed proteins. The peak height of the beta-peak (1639 cm-1) in the amide I band linearly increased with the antiserum concentration as well as that of the amide II band. The detection limit (S/N = 3) was a 1:36 000 dilution for the amide I signal. In addition, through the use of surface-sensitive MIR-FTIR, the present sensor selectively detected the antigen-antibody interactions at the surfaces without being affected by the presence of bulk species, enabling rapid and wash-free detection. Our method provides not only rapid label-free detection of protein-protein interactions but a more accurate discrimination between specific and nonspecific interactions through the use of the secondary structure of the target proteins as a measure for the specific signals |
|---|---|
| Beschreibung: | Date Completed 08.02.2008 Date Revised 24.11.2016 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1520-5827 |