Nanofiber-based fet biosensors produced by electrospinning method for detection of ferritin

Ferritin is a clinically significant biomarker that reflects the body's iron status and is associated with anemia. Serum ferritin level is considered the most specific biochemical test method related to total body iron stores and is the most commonly used indicator of iron status. The ideal serum ferritin concentration is considered to be 12–300 ng/mL for men and 12–150 ng/mL for women. Serum ferritin levels that are significantly lower or higher than these threshold values require continuous monitoring and evaluation of the individual's iron status. However, the conventional methods used for ferritin detection are not portable and have long response times. With the integration of nanomaterials into biosensor platforms, it has become possible to develop sensors with exceptional sensitivity and selectivity capable of detecting even trace amounts of biomolecules. It is known that the incorporation of various types of nanomaterials such as nanoparticles, nanorods, and nanofibers into biosensor platforms enhances sensor performance. Studies have shown that due to their small size, high carrier mobility, large specific surface area, and high surface-to-volume ratio, nanofibers are suitable active materials for various electronic applications. The rapidly advancing semiconductor industry has also demonstrated that Field Effect Transistors (FETs) have potential for the electrical detection of biomolecules. The design and fabrication of FET-based biosensor platforms containing nanofibers are crucial for enabling portable devices, miniature systems, and point-of-care (POC) applications. Such platforms allow for real-time, accurate biomolecule detection with high sensitivity and selectivity, as well as ease of use. In this thesis study, a low-cost Bio-FET platform has been designed by utilizing the superior electrical and optical properties of nanomaterials such as graphene and PVDF nanofibers. The platform is characterized by a low detection limit, flexibility, high selectivity and sensitivity, rapid response, and user-friendly operation. The structural and electrical characterizations of the fabricated biosensor platforms have been conducted.