13 research outputs found
Detection of Quadruplex DNA by Gold Nanoparticles
Gold nanoparticles have been used as a probe to detect low (<10âppb) concentrations of quadruplex DNA. These nanoparticles display a tendency to form aggregates in the presence of certain quadruplex forms, as observed via enhanced plasmon resonance light scattering (PRLS) signals. These nanoparticles showed differing degrees of interactions with different types of quadruplex and mixed sequences but no interaction with duplex DNA. Enhancement of PRLS signals greater than 50% was observed at nanomolar DNA concentration, and a lower limit of detection of 2.1ânM was established for three different quadruplex DNA sequences, including the thrombin-inhibiting single-stranded 15âmer aptamer DNA, d(GGTTGGTGTGGTTGG), and the double-stranded 12âmer DNA, d(G4T4G4). Two different sample preparation protocols were used for the PRLS experiments, and they yielded similar results