Cellular imaging through functionalized carborane-containing silver nanoparticles utilizing surface enhanced Raman scattering spectroscopy

Abstract

This thesis focuses on various carborane compounds and their uses for targeted cellular imaging. Cellular imaging agents have been developed for the field of medical diagnosis and treatment for some time. Many different processes have been traditionally applied in these fields, including fluorescence tagging, but these are lacking in differentiation from cellular background signals. Herein, carborane compounds have been developed for use as Raman reporters with signature absorption for BH vibrations, inside of the cell silence vibrational range. Carboranes have also been studied for the application of Boron Neutron Capture Therapy, a binary radiation therapy technique. Coupling these two ideas has lead to the formation of specific cellular targeting agents utilizing the unique BH vibrations for imaging, as well as the possible application of BNCT to the malignant tissue. This process has been developed with the aid of silver nanoparticles, which have been shown to enhance the Raman signal up to a factor of 1014 with Surface Enhanced Raman Scattering (SERS) techniques. Functionalized carborane compounds have been developed in order to study BH vibrations, and carborane-containing functionalized silver nanoparticles have been applied to target anti-EGFR antibodies for malignant tissue detection. Resulting SERS images confirmed selective tissue targeting with nanoparticle aggregate hot spots. Overlaying scanning electron microscope images with SERS BH vibrational intensity maps provided additional information on concentrations of cell surface receptors and identifying intercellular structures. Elaboration of the carborane Raman reporter resulted in two other carboranes with key functional groups, which could increase solubility, and have additional Raman handles for identification.