Raman Spectroscopic Methods for the Detection of Biomarkers of Neurodegeneration

The research in this dissertation is aimed towards the development of detection methods for neurotransmitters and biomarkers involved in neurological diseases. Neuronal communication in the brain is a cascade of electrical and chemical impulses occurring in the sub-second time scales. As such, detection of physiologically relevant fluctuations in neurological diseases must be highly sensitive, rapid, mitigating exposure to labelling methods, such as radiotracers. We mainly utilize Raman spectroscopy, a light scattering technique, which provides vibrational and rotational mode information in even the most chemically similar molecules. Inelastic or Raman scattering is inherently weak. Hence, to enhance the signal, we utilize a phenomenon known as the localized surface plasmon resonance (LSPR) effect. When irradiated with a light source, collective oscillation of the conductive band electrons at the metal noble nanoparticle surface enhances the electric field. SERS is a powerful technique which allows for the detection of low concentrations of analytes, which is crucial in the physiological relevant range. Here we will discuss the combined optimization and development of various techniques and substrates coupled with Raman spectroscopy to detect neurological disease biomarkers.