Prostate cancer is the most common male cancer in the world. The diagnosis, staging,
prognosis and monitoring are usually done with Prostate Specific Antigen (PSA). Biosensors are
emerging as a novel analytical technology for PSA detection. They provide several advantages for
clinical applications and will benefit clinicians, patients and forensic workers in the future. Among
them, electrochemical immunosensors have gained growing interests. Hence, their sensitivity is often
improved by modifying them with nanoparticles especially iron oxide (IONP). Functionalized
IONP attracted much attention in the fabrication of biosensing systems, due to their multiple properties,
such as biocompatibility and signal amplification, and their ability to bind covalently to antibodies
via their functional groups. In the present study, two electrochemical immunosensors were
investigated for PSA detection. The first one was functionalized with 3- glycidoxypropyltrimethoxysilane
self-assembled monolayer, while the second one was based on iron oxide nanoparticles functionalized
with 3-aminopropyltriethoxysilane. Square wave voltammetry (SWV) has been investigated
to follow-up the PSA detection in a phosphate buffer solution, in an artificial serum and in a
human serum. The limit of detection (LOD) of both immunosensors was found of order of 10 fg/ml.
When estimated in human serum this value increases up to 50 pg/ml.