DNA-conjugated gold nanoparticles based colorimetric assay

We designed a novel assay for the study of helicase activity  based on DNA-conjugated gold nanoparticles. We were able to disentangle the action of RecQ4 helicase and its mutants with this colorometric assay, comparing it with standard and costy fluorescent methods.  Deka et al Scientific Reports, 7, 444538 (2017)

		Helicase are essential enzymes which are widespread in all life-forms. Due to their central role in nucleic acid metabolism, they are emerging as important targets for anti-viral, antibacterial and anti-cancer drugs. The development of easy, cheap, fast and robust biochemical assays to measure helicase activity, overcoming the limitations of the current methods, is a pre-requisite for the discovery of helicase inhibitors through high-throughput screenings. We have developed a method which exploits the optical properties of DNA-conjugated gold nanoparticles (AuNP) and meets the required criteria. The method was tested with the catalytic domain of the human RecQ4 helicase and compared with a conventional FRET-based assay. The AuNP-based assay produced similar results but is simpler, more robust and cheaper than FRET. Therefore, our nanotechnology-based platform shows the potential to provide a useful alternative to the existing conventional methods for following helicase activity and to screen small-molecule libraries as potential helicase inhibitors.		Retrieve articles DNA-conjugated gold nanoparticles based colorimetric assay to assess helicase activity: a novel route to screen potential helicase inhibitors  J. Deha, A. Mojumdar, P. Parisse, S. Onesti, L. Casalis Scientific reports  7, 44538 (2017)