Detailed Study of BSA Adsorption on Micro- and Nanocrystalline Diamond/β-SiC Composite Gradient Films by Time-Resolved Fluorescence Microscopy
The adsorption of bovine serum albumin (BSA) on micro- and nanocrystalline diamond/β-SiC composite films synthesized using the hot filament chemical vapor deposition (HFCVD) technique has been investigated by confocal fluorescence lifetime imaging microscopy. BSA labeled with fluorescein isothiocyan...
Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 33(2017), 3 vom: 24. Jan., Seite 802-813 |
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1. Verfasser: | |
Weitere Verfasser: | , , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2017
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Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Carbon Compounds, Inorganic Fluorescent Dyes Silicon Compounds Serum Albumin, Bovine 27432CM55Q Diamond 7782-40-3 Fluorescein-5-isothiocyanate mehr... |
Zusammenfassung: | The adsorption of bovine serum albumin (BSA) on micro- and nanocrystalline diamond/β-SiC composite films synthesized using the hot filament chemical vapor deposition (HFCVD) technique has been investigated by confocal fluorescence lifetime imaging microscopy. BSA labeled with fluorescein isothiocyanate (FITC) was employed as a probe. The BSAFITC conjugate was found to preferentially adsorb on both O-/OH-terminated microcrystalline and nanocrystalline diamond compared to the OH-terminated β-SiC, resulting in an increasing amount of BSA adsorbed to the gradient surfaces with an increasing diamond/β-SiC ratio. The different strength of adsorption (>30 times for diamond with a grain size of 570 nm) coincides with different surface energy parameters and differing conformational changes upon adsorption. Fluorescence data of the adsorbed BSAFITC on the gradient film with different diamond coverage show a four-exponential decay with decay times of 3.71, 2.54, 0.66, and 0.13 ns for a grain size of 570 nm. The different decay times are attributed to the fluorescence of thiourea fluorescein residuals of linked FITC distributed in BSA with different dye-dye and dye-surface distances. The longest decay time was found to correlate linearly with the diamond grain size. The fluorescence of BSAFITC undergoes external dynamic fluorescence quenching on the diamond surface by H- and/or sp2-defects and/or by amorphous carbon or graphite phases. An acceleration of the internal fluorescence concentration quenching in BSAFITC because of structural changes of albumin due to adsorption, is concluded to be a secondary contributor. These results suggest that the micro- and nanocrystalline diamond/β-SiC composite gradient films can be utilized to spatially control protein adsorption and diamond crystallite size, which facilitates systematic studies at these interesting (bio)interfaces |
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Beschreibung: | Date Completed 24.09.2018 Date Revised 24.09.2018 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 1520-5827 |
DOI: | 10.1021/acs.langmuir.6b04177 |