Figure 1.

The onset of nanotechnology in virus detection applications compared with the development of the most common virus detection techniques. Cell culture and electron microscopy techniques that are now commonly applied in the direct testing for and detection of viruses were discovered in the mid-20th century ²⁵. Then, different serological and molecular techniques were developed. The serological detection of viruses with immunoassays was first reported in 1970: a radioimmunoassay was applied for the detection of the Australia antigen, later called hepatitis B virus surface antigen ²¹⁸. PCR was discovered in the 1980s and first reported in virus detection in 1988 for acquired immune deficiency syndrome detection ²¹⁹. Later, many molecular techniques, including amplification- and nonamplification-based techniques, were reported in virus detection. The concept of nanotechnology was envisioned as early as 1959 by the renowned physicist Richard Feynman ³⁶. However, nanotechnology was only applied to virus detection in 1997, when gold nanoparticles were employed for the detection of single-copy human papillomavirus ³⁹. Nanotechnology has recently come to represent one of the most outstanding trends in virus detection and diagnosis via the wide variety of assays described in this review.