DNA-Templated Single Thermal Cycle Based Synthesis of Highly Luminescent Au Nanoclusters for Probing Gene Expression

Abstract

Gene expression controls and commands cellular functions of organisms and is considered to be the prime marker of human health. Conventional laboratory techniques use organic dyes as probes for diagnosis, which are mostly toxic, considered as environmental hazards and also known to be carcinogenic. On the other hand, there is a unique opportunity for the development of facile techniques for performing sensitive detection of polymerase chain reaction (PCR) products by biocompatible nanomaterials, especially useful for on-site analyses in a resource-limited location. We report a rapid (2 min) one-step green synthesis of highly luminescent gold nanoclusters on dsDNA, using a single heating and cooling cycle like in PCR. The luminescence intensity of nanoclusters was found to increase with the amount of dsDNA, offering a convenient way for quantification of the dsDNA (PCR products). The ability of the gold nanoclusters to act as powerful probe for DNA quantification was demonstrated in two different cancer cell lines, namely, HeLa and A549.