Problem
DNA cleavage or nuclease activity detection is important in many forms of nucleic acid amplification tests. The current detection technologies rely on the use of fluorescence resonance energy transfer (FRET) reporters that light up upon digestion, such as the Taqman® probe and the DNaseAlert®. Although these FRET reporters well serve the purpose, the need for dual labeling and purification during manufacturing causes FRET reagents to be very expensive.
Solution
Professor Tim Yeh and his team have developed novel fluorescent reporters based on a special class of nanomaterials, DNA-templated silver nanoclusters (DNA/AgNCs), for nuclease activity detection. The DNA/AgNCs described in this invention are low-cost, organic-inorganic complex fluorophores whose emission spectra are sensitive to nucleobases around cluster cores. When template DNA is digested, conformational and stoichiometric changes occur in the core clusters, resulting in a color change of the DNA/AgNC reporter. The DNA/AgNCs are highly fluorescent with quantum yields up to 0.9 and extinction coefficients of ~105 M-1cm-1 and multicolor with emission peaks ranging from 300 to 950 nm. The DNA/AgNCs are activatable, color-tunable, environmentally sensitive, and biocompatible. The product can be manufactured at 1/100 of the cost of a dual-labeled FRET probe and are easy to prepare using a one-pot reaction at room temperature.
About the inventor
Dr. Yeh is an Associate Professor of Biomedical Engineering at the Cockrell School of Engineering at UT Austin. His area of expertise is focused on nanobiosensor development, cancer biomarker detection, single-molecule spectroscopy for biomolecule and nanomaterial characterization, 3D molecular tracking, and super-resolution imaging.
