Applications of gold nanoparticles in virus detection

Draz, Mohamed Shehata; Shafiee, Hadi

The family Filoviridae can be classified into two main genera, Ebolavirus [119, 122] . Filoviruses are filamentous, enveloped RNA viruses 80 nm in diameter and approximately 800-1000 nm in length. Their genome is nonsegmented, negative-sense, ssRNA 19 kb in size that encodes for at least 7 proteins (nucleoprotein, viral proteins VP24, VP30, VP35, and VP40, glycoprotein, and polymerase protein) [123] . AuNPs stabilized by single-stranded (ss)DNA probes. In the presence of the target DNA sequence, double-stranded (ds)DNA is formed and desorbs from the surface of citrate-reduced AuNPs, leaving them to aggregate. This aggregation results in a color change from red to blue, indicating the presence of target nucleic acids [54, 56] . (B) Enzymatic electrochemical detection of SARS by anodic stripping voltammetry using a AuNP-screen-printed carbon electrode. The AuNP-modified electrode is modified with capture DNA probes that are allowed to hybridize with biotinylated targets. Streptavidin-alkaline phosphatase (S-AP) is then applied for the indirect reduction of silver ions in the solution into a metallic deposit. The formed silver metals are then electrochemically measured to determine the target virus DNA concentration [72] .