Resonance light scattering determination of uranyl based on labeled DNAzyme-gold nanoparticle system

A resonance light scattering (RLS) method has been developed using a uranyl (UO22+) specific DNAzyme and gold nanoparticles (AuNPs). In this strategy, the cleavage of the substrate strand (SDNA) of DNAzyme results in releasing a shorter duplex in the presence of UO22+, leading to the aggregation of AuNPs and the increase of RLS intensity. The response signals linearly correlated with the concentration of UO22+ over the range of 1.36 x 10(-8)-1.50 x 10(-7) mol L-1. The limit of detection (LOD) is 4.09 x 10(-9) mol L-1. The method has excellent selectivity and higher sensitivity. It could provide a promising potential for the detection of metal ions, and be benefit to extend the application of RLS method. (C) 2013 Elsevier B.V. All rights reserved.