Fluorescent silver nanocluster DNA probes for multiplexed detection using microfluidic capillary electrophoresis

DNA-stabilized fluorescent silver nanoclusters (AgNC DNA) are a new class of fluorophore that are formed by sequence specific interactions between silver and single-stranded DNA. By incorporating both target-binding and fluorescent-reporting sequences into a single synthetic DNA oligomer, AgNC DNA probes eliminate the need to conjugate dye or quencher molecules. In this study, we modify a AgNC DNA probe to demonstrate single-color multiplexed detection of DNA targets. We show that appending different lengths of poly-dT to the probe sequences tunes the electrophoretic mobility of AgNC DNA probes without affecting their fluorescence spectra. We use this to introduce a set of AgNC DNA probes selective for Hepatitis A, B and C target sequences that can be processed together in a simple, single-step protocol and distinguished with a resolution of 3.47 and signal to noise ratio of 17.23 in under 10 seconds by microfluidic capillary electrophoresis.

J. T. Del Bonis-O’Donnell, D. K. Fygenson, and S. Pennathur
The Analyst
Volume: 140
Number: 5
Pages: 1609-1615
Date: January, 2015
ICB Affiliated Authors: Sumita Pennathur