Single Particle Characterization and Total Elemental Concentration Measurements in Polar Ice Using Continuous Flow Analysis-Inductively Coupled Plasma Time-of-Flight Mass Spectrometry
Erhardt, T.; Jensen, C.; Borovinskaya, O.; Fischer, H
Environmental Science & Technology
DOI: 10.1021/acs.est.9b03886
In this study, the icpTOF R was used for the first time in combination with the continuous flow analysis (CFA) to analyze dissolved ions and individual dust particles in polar ice.
In the CFA, the ice core vertical cut is continuously molten, separating the clean melt water from the contaminated outer part of the ice. The clean water is then either collected in fractions or analyzed directly online. Dissolved ions are typically measured by spectrophotometric or fluorometric techniques and insoluble particles by laser light extinction.
ICP-MS is used in the CFA for determination of trace elemental concentrations. The CFA yields high depth resolution which directly translates into time resolution in seasonal variability of the aerosol deposition. Therefore, it is very important to preserve this resolution throughout the entire analysis.
The icpTOF R measures all elements simultaneously and its sensitivity does not depend on the number of chosen isotopes. Therefore, the icpTOF R is highly suitable for detection of fast changing signals, such as those generated in the CFA. The authors showed that the icpTOF R provides similar or better resolution than the established spectrophotometric methods. Along with the analysis of total elemental concentrations, the instrument was applied to measure the relative elemental composition of individual mineral dust particles. The analysis of iron-containing particles revealed that most of these particles in the Greenland ice are clay minerals.
Using the the icpTOF R in combination with CFA analysis, researchers were able to:
- Analyze a wide range of elements at good resolution.
- Identify sources of dust particles through characterization of the individual particles.Â