Abstract: A sample support for polymer-spray mass spectrometry includes a support substrate comprising a polymer. The support substrate is configured to support a sample on a surface of the support substrate. The sample support also includes a reservoir formed on the surface of the support substrate. The reservoir is configured to hold a spray solvent.

Abstract: Aspects of the invention include methods for reducing a pathogen population. Methods according to certain embodiments, a source of the pathogen is contacted with a plurality of microdroplets having one or more reactive oxygen species. In certain embodiments, methods include producing the microdroplets by outputting an aqueous composition from an orifice of a flow channel to produce a plurality of microdroplets having one or more reactive oxygen species. In certain embodiments, methods include producing microdroplets through the condensation of water by contacting solid carbon dioxide with an aqueous composition such as by dropping the aqueous composition on the solid carbon dioxide or submerging the solid carbon dioxide in the aqueous composition to produce a plurality of microdroplets having one or more reactive oxygen species. Compositions of a plurality of microdroplets having one or more reactive oxygen species are also provided. Systems for practicing the subject methods are also described.