We report the label-free detection and sizing by a microcavity of the smallest individual RNA virus, MS2, with a mass only ∼1 of InfluenzaA (6 vs. 512 ag). Although detection of such a small bio-nano-particle has been beyond the reach of a bare spherical microcavity, it was accomplished with ease (S/N 8, Q 4 × 10 5) using a single dipole stimulated plasmonic-nanoshell as a microcavity wavelength shift enhancer, providing an enhancement of ∼70×, in agreement with theory. Unique wavelength shift statistics are recorded consistent with an ultra-uniform genetically programmed substance that is drawn to the plasmonic hot spots by light-forces.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)