Green Synthesis of Nanoparticles and their Utilization in Electrochemical Detection of Catechol- or Phenol-Based Substances

Daniel Laurence Myers III, Wright State University


PART A: GREEN SYNTHESIS OF COPPER NANOPARTICLES AND THEIR UTILIZATION IN THE DETECTION OF NEUROTRANSMITTERS Neurotransmitters, such as dopamine and epinephrine, are chemicals frequently found in the brain and are responsible for a number of human moods, needs, and emotions.1, 2 Detection of such neurotransmitters allows for a better judgement of a person’s physical and mental state, a utility that is vital in determining the presence of disease and mental illnesses.2 Electrochemical detectors used for such detections are often modified by materials such as metal nanoparticles.3 However, synthesizing nanoparticles can involve or produce chemicals, ammonium hydroxide among them, that are not safe for the environment.4 The goal of this research was to synthesize copper oxide nanoparticles utilizing environmentally-friendly techniques involving lemon juice and to detect dopamine and epinephrine in the presence of an interferant, ascorbic acid, using those nanoparticles. Creation of the nanoparticles, confirmed by a UV-Vis, indicated a successful synthesis. Voltametric analyses utilizing these nanoparticles display an improvement to detection of the neurotransmitters and indicate the possibility of further improvements to the methods of synthesis to better produce nanoparticles for this particular purpose. iii Part B: GREEN SYNTHESIS OF SILVER NANOPARTICLES AND THEIR UTLIZATION IN THE DETECTION OF PHENOLS A second unrelated research study included in this thesis is the development of a silver nanoparticles attached to a carbon electrode to detect phenol, a carcinogen and pollutant, electrochemically. The silver nanoparticles (AgNPs) were synthesized in an environmentally-friendly method utilizing honey. The successful synthesis of the AgNPs was confirmed by UV-Vis spectroscopy before being utilized to detect phenol. Phenols are extremely harmful to humans and aquatic organisms, thus making development of a sensor that is compact, easy to transport and capable of quickly and accurately detecting them in trace amounts utilizing electrochemistry is of interest. Voltametric techniques were utilized to detect trace amounts of phenol at various pH values using the modified AgNPs electrode. The detection of phenol by differential pulse voltammetry was found to be most effective near pH of 7 with the AgNPs electrode.