| dc.description.abstract | In recent years, with the development of medical related domain, the diagnosis and treatment of diseases require a series of analysis and discussion through instrument detection. Pursuing a high-sensitivity, short reaction time, and label-free biomolecule detection platform is a common goal for everyone. In order to achieve this goal, not only the more sensitive detection instruments, but the detection surface must also avoid the interference of non-specific adsorption. These non-specific substances are usually come from the non-specific adsorption of proteins, especially in clinical testing, detecting sample from complex systems such as physiological fluids (blood, serum, urine). The fouling surface may decrease the sensitivity of the biosensor , affecting the specificity and reproducibility, and increase the background signal. In this way, it further illustrates the importance of antifouling.
In this study, we modify poly (ethylene glycol) (PEG) to the surface by self-assembled monolayer (SAM). EG monomer can capture the water molecules by hydrogen bonds to form a dense water layer, which forms a barrier against non-specific protein adsorption. We detect the adsorption of non-specific substances and interference tests in serum by surface plasmon resonance image (SPRi). By the experimental results, the mixed SAM solution of SH-PEG-NH2 : SH-PEG-OH=1:20 (total concentration of 1mM in absolute ethanol), has an excellent antifouling ability with lower than 1 ng/cm2 nonspecific adsorption from single protein and diluted serum. Furthermore, the SPR sensor could successfully detect the biomolecule in diluted human serum in the interference test. After getting the optimal condition from SPR, we apply it to FET. We could clearly detect 0.1 nM of the target in 1% serum by FET. Therefore, in this study, the surface we developed provides the best conditions for detecting biomolecules and reducing non-specific adsorption in complex biological media, providing a promising surface for clinical diagnostic platforms, allowing for more accurate diagnosis early and give the proper treatment. To create a large platform for precision medical testing with this model. | en_US |