Biomedical applications of nanowire-based nanosensors

In this thesis, nanomaterials, their fields of use, and importance in various applications are explained. Classification based on dimensionality and the variety of morphologies resulting from varying aspect ratios is reviewed. Nanomaterial properties such as electrical, magnetic, surface, thermal, and optical properties, which classical physics cannot be applied to due to sizes down to the nanoscale, are further examined. TEM and SEM microscopy methods used in the examination and evaluation of nanomaterials and nanowires are briefly demonstrated. Then, the synthesis of nanowires using methods such as laser ablation, thermal evaporation, chemical beam epitaxy (CBE), molecular beam epitaxy (MBE), and oxide-assisted growth (OAG) is followed by the alignment of produced nanowires through Langmuir-Blodgett (LB) alignment, bubble-blown (BB) alignment, electric field, and current-assisted alignment, which are further reviewed. Nanowire FETs produced using aligned nanowires are compared with conventional FETs. Silica nanowire FETs as sensor interfaces and their usage as nanobiosensors are thoroughly researched. Various surface functionalization methods done on nanowire surfaces to interact with target analytes are explained. Precise and highly sensitive detection of biological analytes such as DNA, microRNA, proteins, single viruses, and enzymes with nanowire nanobiosensors is achieved by analyzing obtained conductivity change data. Corresponding TEM, SEM images, and conductivity graphs of the related experiments are also presented. Among these wide varieties of applications, detection of coronavirus with nanowire FETs and the concept of the internet of nano things to provide a means of transferring the obtained data to data centers are further explained.