AVS 54th International Symposium | |
Biomaterial Interfaces | Thursday Sessions |
Session BI-ThP |
Session: | Biomaterial Interfaces Poster Session |
Presenter: | E.N. Newman, University of Washington |
Authors: | E.N. Newman, University of Washington F. Cheng, University of Washington L.J. Gamble, University of Washington K. Bomsztyk, University of Washington D.G. Castner, University of Washington |
Correspondent: | Click to Email |
Surface treatment of polypropylene with plasma polymerized acrylic acid (PPAA) has been used to fabricate an immunosensor. This study examines both the amount and the bioactivity of the immobilized antibody. A comparison of PPAA - based strategy to the traditional coupling chemistry onto self-assembled monolayers was done using X-ray photoelectron spectroscopy (XPS) and surface plasmon resonance (SPR). XPS results for the PPAA surfaces indicate that 1) PPAA can be deposited onto various substrates (e.g., polypropylene, Si wafer and gold), 2) ~ 50% of the low-power, deposited PPAA film dissolves after soaking overnight in water, and 3) the N-ethyl-N'-(3-dimethylaminopropyl) carbodiimide / N-hydroxysuccinimide method activates carboxyl groups at PPAA surface and allows proteins to be coupled to it. SPR provides a quantitative comparison of the amount of anti-ferritin immobilized by two strategies and the amount of ferritin the immobilized anti-ferritin binds. In addition, time-of-flight secondary ion mass spectrometry (ToF-SIMS) is used to investigate the structure of the PPAA surface as well as the structure of the immobilized anti-ferritin. Our results suggest that the PPAA - based strategy improves the biological activity and stability of the immobilized antibodies.