Atmospheric Sampling Mass Spectrometers Activate and Ionize Neutral Water Microdroplets to MeV Energies and up to 200,000+ Charges: Implications for Water Stability and Unusual Chemistry in Microdroplets.

ABSTRACT: Neutral water microdroplets formed by condensation were introduced into a mass spectrometer with a standard stainless-steel capillary atmospheric interface. Placing volatile samples near the mass spectrometer inlet led to spectra comparable to those of electrospray ionization of the same compounds. Neutral microdroplets introduced into a charge detection instrument through a nearly identical atmospheric sampling interface resulted in charged microdroplets with diameters between 165 nm (∼3,000 charge detection threshold) and 2.8 μm (200,000+ charges). The vast majority of 100,000+ aqueous microdroplets analyzed were positively charged. Aerodynamic acceleration led to average velocities of ∼270 m/s and ∼210 m/s for the smallest and largest microdroplets, respectively, with corresponding ener

SUBMITTER: McPartlan MS 

PROVIDER: S-EPMC12746156 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature