The present disclosure describes methods of detecting viral biomolecules such as viruses through frequency response. A method (200) of detecting a vims includes exposing (210) a sensor surface to a fluid sample containing a suspected virus. The sensor surface can be a surface of a resonator having a clean resonant frequency from about 1 MHz to about 1 GHz. The surface can be modified with molecular recognition groups selective for binding to the viral biomolecule. A resonant frequency of the resonator can be measured (220) after exposing the sensor surface to the fluid sample. The measured resonant frequency can be compared (230) with a clean resonant frequency indicating the presence of the viral biomolecule bound to the molecular recognition groups and then outputted (240) as a detection signal.

A method and apparatus used to determine atmospheric extinction coefficients in conjunction with an unmanned aerial vehicle are provided. The unmanned aerial vehicle may include a central body, at least one motor operatively connected to the central body, a condensation particle detection payload, and a data acquisition board including memory operatively connected to the data acquisition board, and a processor configured to generate extinction information.