REVS: Good vibrations

A paper in last week's issue of Nature Biotechnologymay offer an alternative to PCR amplification in detecting viruses. Researchers at the University of Cambridge detected herpes simplex virus (HSV) using a quartz crystal microbalance, which they said is quantitative over at least six orders of magnitude and did not require an amplification step.

The researchers covalently attached anti-HSV antibodies to the crystal, and virus was run over the antibody surface, where it became bound. The quartz was made to oscillate using an electric field, and the oscillation amplitude was increased until HSV detached from the antibody. Each dissociation, or rupture event, produced a sound, and the intensity of the sound was shown to be proportional to the number of viruses involved. ...