李剑君

Date:

2025-04-30

Title of Paper:

Effect of gold nanoparticles on the fluorescence excitation spectrum of_-fetoprotein: Local environment dependent fluorescence quenching.

Journal:

Spectrochimica Acta Part A

Summary:

The effect of colloid gold nanoparticles (AuNPs) on the fluorescence excitation spectrum of -fetoprotein
(AFP) has been investigated experimentally. The excitation spectral peaks of AFP with low concentration
from 0.01 ng ml−1 to 12 ng ml−1 increase monotonically with increasing of AFP concentration. When
some gold colloids were added to the AFP solution, the excitation peak at 285nm decreases distinctly.
By comparing the excitation peak intensity of AFP solution with gold colloids and without gold colloids
at different AFP concentrations, the quenching effect from gold nanoparticle was more effective at lower
AFP concentration. So the range of concentration from 0.01 ng ml−1 to 0.09 ng ml−1 will be the potential
range of applications because of the higher sensitivity. The physical origin based on local field effect
was investigated to illuminate this local environment dependent fluorescence quenching. The changing
extent of quenching with different AFP concentrations can be attributed to the nonlinear decreasing of
the local field factor of gold nanoparticles as a function of environmental dielectric constant.

Co-author:

Jian-jun Li, Yu Chen, A-qing Wang, Jian Zhu

Translation or Not:

No

Date of Publication:

2011-05-01