Fabrication And Performance Analysis Of Biosensors Based On Different Hybrid Nanomaterials

ECL biosensors are quite sensitive and excellent for detecting different types of biomolecules, due to its advantages, including simple setup, easy process, fast response, long range detection, and its possibility to be automatic. Hence, this new type of biosensor attatacted lots of scientists’ focus. In this thesis, ECL biosensors based on different nanomaterials were designed, optimized, fabricated and utilized in the detection of human cancer cells. Through the fantastic results, this biosensor offered a nice platform for the clinical applications.Basically, several aspects were conducted in this dissertation:Fluent software was utilized for the optimization and calculation of the microfluidic chips based on CFD method, followed by the fabrication of these chips using PDMS as the material. The optimization includes the following conditions: the optimal structure with the injection angle of 120°, and the best flow rate.Based on the optimizedconditions obtained by simulations, and the chemical reaction between NH3H2 O and Ce（NO3）2, two flows of these two solutions were injected into microfluidics channels, where the reaction occurred with the product of CeO₂. By tuning the outside parameters of temperature and flow rate, the morphology of CeO₂ nanomaterial was well controlled and adjusted. Based on the best material, Cd S@CeO₂ material was fabricated using ionic layer absoprion method, which was further confirmed by UV-vis, EDS, and SEM. Hence, a novel ECL biosensor was fabricated based on the above material using Layer-by-layer technique. This biosensor can detect different cancer cells with the range of 1000-5000 cell /m L, with the detection limit of 1210.Since the biosensor based on Cd S-CeO₂ nanomaterial has narrow detection range, more research were carried out to explore a novel material. SiO₂ was synthesized and characterized using UV-vis spectra, EDS and SEM. Then, Cd S@SiO₂ material was fabricated using ionic layer absoprion method, which was further confirmed by UV-vis, EDS, and SEM, as well. Hence, a novel ECL biosensor was fabricated based on the above material using Layer-by-layer technique. This biosensor can detect different cancer cells with the range of 300-14000 cell /m L.Since the biosensor based on Cd S-SiO₂ nanomaterial needs tobe fabricated by sealing. A novel material based on Cd S modified foam nickle was fabricated and utilized for the detection of cancer cells directly, which was further confirmed by UV-vis, EDS, and SEM, as well. Hence, a novel ECL biosensor was fabricated based on the above material using Layer-by-layer technique. This biosensor can detect different cancer cells with the range of 200-10000 cell /m L, with the detection limit of 78. This sensor was estimated with its stability, reproducibility, and selectivity. From the results, we can see that the stability was not as good as the one based on Cd S-SiO₂, because this biosensor was not sealed after fabrication.