Nanomaterial modified electrode surface characterization and biosensor application for a terrorism agent detection

Although nerve agents are the most notable among chemical agents, they show their negative effects mainly in nervous tissue. Toxic chemical substances, which have basic properties such as killing people and other living things, destroying them with serious injury, and rendering them ineffective by disrupting their functions, have high toxic potential, are resistant to external factors, and are economical to produce, are generally defined as chemical weapons. Organophosphorus pesticide poisoning has become a global health problem affecting millions of people with acute and chronic poisonings, as the possibility of exposure to chemical nerve gases through terrorist and military activities has also become a serious threat to our soldiers. To date, many studies have been carried out for the detection of Organophosphorus pesticides, but although these techniques are selective and sensitive, disadvantages such as expensiveness, advanced personnel, and preparation processes limit the applications of on-site analysis, especially in emergency situations such as accidental pesticide release. Therefore, there is an urgent need for fast, sensitive, reliable, and cost-effective detection tools for environmental, security, military, and biomedical monitoring. In this master's thesis, the biosensor system and carbon nanotubes, reduced graphene oxide, and graphene nanomaterials, which will be the basis of the system, were used because of their unique properties. In this thesis, Carbon nanotube, graphene, and reduced graphene oxide nanoparticles were modified on the Carbon screen printed electrode surface using drop casting and electrodeposition techniques. Then, an enzyme inhibition-based biosensor system was developed for paraoxon, a terrorist agent, detection. Biosensor performance conditions under optimum conditions were investigated. It was concluded that the developed nanoparticle-based biosensor system would enable faster, cheaper, more sensitive, and real-time tests and show more linear detection range and stability efficiency than existing studies for the detection of the terrorist agent paraoxon.