Nanostrutture di oro per applicazioni in imaging e per il test ELISA usando l' effetto SERRS

In this thesis were synthesized gold nanostructures suitable for recognition of specific antigens that are overexpressed by tumor cells of prostate cancer. Gold nanoparticles with a diameter of approximately 20nm were obtained from a massive diskette with a top-down method: laser ablation in solution. The nanoparticles thus created, dispersed in water and free of surfactant molecules on their surface, were then aggregate. These aggregates, used as a substrate, were then functionalized with an antibody and a dye to simultaneously perform targeting and imaging. Five preparations have been used in ELISA sandwich immunoassay in order to increase its sensitivity. In the present project are reported the results of one of these five preparations on which the antibody was used for the recognition of PSMA antigen. After performing ELISA test with a procedure very similar to the classic one, the contents of the various wells was filtered on a membrane above which subsequently, using SERRS spectroscopy, the spectra of the dye with which the preparation was functionalized were registered. The data obtained showed a trend similar to those of the classical test and it shows that the nanostructures created have good targeting capabilities, also the sensitivity was increased by 2 times. Encouraging results have also been obtained with the imaging in multiplexing mode of tumor cells of prostate cancer. The two preparations used, different for the type of antibody and for the dye with which were functionalized, have shown a good targeting ability and the SERRS signals were intense and suitable for imaging in multiplexing mode.