A facile method for the detection of DNA by using gold nanoparticle probes coupled with dynamic light scattering
The Education Ministry Key Laboratory of Resource Chemistry, Department of Chemistry, College of Life and Environmental Sciences, Shanghai Normal University, 100 Guilin Road, Shanghai, 200234, China
Nanoscale Research Letters 2012, 7:564 doi:10.1186/1556-276X-7-564Published: 10 October 2012
In this paper, we present a simple and rapid method for deoxyribonucleic acid (DNA) detection using gold nanoparticle probes coupled with dynamic light scattering (DLS) analysis. The redox agent 1,4-dithio-DL-threitol cross-links the gold nanoparticles (AuNPs) to form clusters, while the monothiol DNA could terminate the formation and stabilize the assembled clusters by their negatively charge-based repulsions. By varying the concentration of DNA, the different sizes of DNA-AuNP clusters can be obtained. The sizes of the DNA-AuNP clusters were determined by DLS. A linear correlation was obtained between the sizes and the logarithm of DNA concentration from 2 nM to 5 μM with a detection limit of 1 nM (S/N = 3).