Synthesis and applications of plasmonic metal nanostructures

• Main Author: Tan, Jillian Jing Wen.
• Other Authors: Xue Can
• Format: Final Year Project
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering::Materials::Nanostructured materials
• Online Access: http://hdl.handle.net/10356/51461
• Institution: Nanyang Technological University

More than 12.6 million people in the world are diagnosed with cancer every year, with at least 7.5 million dying of this disease (1). A research by the World Health Organization stated that this figure continues to rise in every country as the population grows and people live longer. Fluorescence is one of the most important tools for cancer cells detection. However, its sensitivity is limited by certain problems such as photobleaching, narrow excitation with broad emission profiles, and peak overlapping in multiplexed experiments (2). Two studies related to metal enhanced fluorescence (MEF) were analyzed. The fluorescent dye molecules showed strong plasmonic interactions with a metal core which increases the fluorescence signal. This phenomenon is observed between a metal core and metal nanoparticles as well. Combining the ideas from the research, this project aims to create a dye-embedded silica shell coated with metal nanoparticles. The silica shell was used to control the distance between the dye and metal. The amount of nanoparticles had to be varied as well to achieve optimum fluorescence enhancement. A 24nm shell thickness with 20ul of nanoparticles produced the best result in this experiment. This can be further improved by varying the values continuously and including other factors which will affect the intensity. With this enhancement in fluorescence signals, cancer cells can be detected more easily and patients can be treated at an earlier stage.