Biodetection Based on Fluorescence Quenching and Surface-Enhanced Fluorescence Using Noble Metal Nanoparticles - From Bioimaging to Biosensors: Noble Metal Nanoparticles in Biodetection - page 211

Chapter 10
Biodetection Based on Fluorescence
Quenching and Surface-Enhanced
Fluorescence Using Noble Metal
Nanoparticles
Yang-Wei Lin a , Chi-Wei Liu b , and Huan-Tsung Chang b, *
a Department of Chemistry, National Changhua University of Education,
1, Jin-De Road, Changhua City 500, Taiwan
b Department of Chemistry, National Taiwan University,
1, Section 4, Roosevelt Road, Taipei, Taiwan
* [e-mail]
Fluorescence is popular in carbohydrate, protein, and DNA arrays;
cell imaging; and single molecule detection because of its sensitivity.
To achieve high sensitivity, luorophores possessing high quantum
yields are necessary. However, most analytes do not luoresce
strongly. In order to overcome this shortage, techniques based on
luorescence quenching and surface-enhanced luorescence using
novel metal materials have been applied. Fluorescence quenching and
enhancements are both dependent on the distance of luorophores
from the metal surface; quenching usually occurs at a distance no
greater than 50 Å while luorescence enhancement commonly takes
place at a distance between 70 and 100 Å. In addition to distance, the
nature, size, and shape of metal materials are important parameters
for luorescence quenching and enhancement. With advanced
nanotechnology, researchers have demonstrated techniques