Applications of gold nanoparticles in virus detection

Draz, Mohamed Shehata; Shafiee, Hadi

AuNPs have been combined with the well-known analytical techniques QCM and ICP-MS to develop two novel molecular assays for DENV detection. For the first time, these assays implemented AuNPs to increase the mass of target DNA to allow its detection by QCM in a highly quantitative and sensitive manner (Fig. 7A) or to amplify the detection signal by releasing many gold ions during ICP-MS analysis of the target DNA (Fig. 7B ). In the AuNP-based QCM assay, the presence of target DNA initiates a layer-by-layer hybridization of the target DNA and several specific multivalent AuNP-DNA probes, resulting in significant mass changes detected by QCM [93] (Fig. 8A) . Whereas, in the ICP-MS-based assay, two types of probes prepared from specific AuNP-DNA and MNP-DNA conjugates are applied to specifically recognize and sandwich the target virus DNA sequences. The MNP probes then help to magnetically separate the formed sandwich complexes, and the target DNA concentration is indirectly estimated by detection of the Au concentration existing in the sample [94] (Fig. 8B) .