The SARS-CoV-2 virus is a member of the Coronaviridae family that emerged in late 2019 and caused the COVID-19 pandemic. Monodisperse silica particles have interesting optical properties in solutions that could be used in the design of a biosensor for virus detection. One of the most important steps in biosensor production is the functionalization of the particles with molecules that allow the detection of target molecules. In this thesis, the structural N protein and the accessory protein ORF8 were investigated. Both proteins inhibit the host immune response and are highly immunogenic. The proteins were expressed in E. coli BL21[DE3]. Using nickel affinity chromatography, only protein N was isolated from the soluble fraction. Moreover, the hexahistidine tag was cleaved by TEV protease, and the N protein was additionally concentrated. Monodisperse SiO2 particles were synthesized in two ways, activated with aldehyde functional groups, and functionalized with the N protein. Protein binding to the particles was demonstrated, but the high sensitivity of the assay method used did not provide clear evidence that the covalent coating was better than the adsorption.
|
