Development of disposable electrochemical immunosensor systems for the determination of ovarian cancer biomarkers

In this thesis, three separate label-free electrochemical immunosensor systems were developed for the early diagnosis of ovarian cancer. First, the transducer parts of CA125 immunosensors were prepared. For CA125 immunosensors, SPCEs were electrodeposited with PTBs prepared in DES and then AuNPs (SPCE/PTBDES/AuNP). In the second step, SPCEs were modified with MXene-COOH for HE4 immunosensors and then AuNPs were electrodeposited (SPCE/MXene-COOH/AuNP). Finally, in the preparation of AFP immunosensors, SPCEs were electrodeposited with PAADESs prepared in DES and then AuNPs (SPCE/MWCNT-COOH/PAADES/AuNP). Electrochemical, chemical, and morphological characterizations of the prepared electrodes were performed. In the design of CA125 immunosensors, a stable SAM layer was formed with 4-MOH and CTES, and immunosensors were also incubated with Anti-CA125, BSA and CA125. In the design of HE4 immunosensors, long carbon chains were formed with 6-MHA and incubated with Anti-HE4, BSA, and HE4. In the design of AFP immunosensors, silanization was performed with 6-MOH and APTES, and incubated with Anti-AFP, BSA, and AFP. Optimum working conditions, analytical performances, and real sample analysis studies of the prepared immunosensors were also performed. Immunosensor systems developed with disposable electrodes are candidates for POCT use in the future.