Metal-enhanced fluorescence detection of biomolecules realized by large-area novel metal nanopattern

Abstract

Highly sensitive and precisely specify detection technique is one of the most interesting research topics in biotechnology since the essential capabilities it has. Among the various methods to detect the biomolecules effectively, fluorescence-based method is very typical and popular way for detection or identification of biomolecules such as DNAs. Several techniques are developed to enhance the efficiency and capacity of fluorescence detection, and the metal-enhanced fluorescence (MEF) system can be one of the excellent means. In this thesis, we introduce the large-area novel metal nanopattern as substrates for MEF system which caused by LSPR effect, and it provides the great enhancement of the detection power for very low concentration of fluorophore. Because the target fluorophores are Cy3 and Cy5 in this study, which have the emission wavelength at about 570nm and 670nm, silver and gold are chosen to match the LSPR wavelength with the emission of target fluorophores. By using CFL process, well-defined metal nanopattern was formed in large-area and the assembly of polyelectrolyte (PET) films provided the proper modified surface for stable immobilization of single strand DNAs. Fluorescence detection results for various concentrations show that the extremely low concentration of target DNA molecules (~ $10^{-11}$ M) detection is possible from the optimally constructed MEF system. Highly enhanced detection limit of biomolecules will contribute to the precise and effective analyze in the fields of diagnosis or advanced biomolecular engineering.