Mass spectra of micrometer-size glycerol droplets containing dissolved inorganic were by on-line laser desorption/ionization. The of quantitation ions in the spectra allowed anioa concentrations in solution to be determined. Liquid droplets have several for quantitative work including well-defined morphology, reproducible matrix composition surrounding the and straightforward preparation of calibration aerosols having known amounts of analyte. Therefore, quantitation can be achieved without an internal standard. Droplet-to-droplet variations of the from 14 to 58%. An improvement of N1/2 in the signal-to-noise ratio was achieved by averaging the spectra of N droplets. Calibration plots of Intensity versus ion concentration in solution were obtained for five test ions; Fe3+, Na+, Cl-, NO3 -, and SO4 2-. The plots were linear over at 2 orders of magnitude in concentration. Minimu detectable cencentration were in the low 10-2 to 10-5 M range, At the minimum detectable concentrations, the absolute amounts of analyte in a single droplet were on the order of 10-16-10-18 mol. Potential applications of methodology to real-time measurements of atmospherically relevant aerosols is discussed.
|Original language||English (US)|
|Number of pages||7|
|State||Published - 1994|
ASJC Scopus subject areas
- Analytical Chemistry