Element XR HR-ICP-MS
High-resolution sector-field mass spectrometry for low-level elemental and isotope-ratio measurements.
Instrument overview
The Thermo Scientific Element XR is a high-resolution sector-field inductively coupled plasma mass spectrometer. Its multiple mass-resolution modes can physically separate some polyatomic interferences and support measurements from trace to matrix-element concentrations.
The proposed analytical program is organized around four matrix- and purpose-specific methods rather than one universal “trace elements” method. Sample preparation, contamination risks, interferences, reference materials, extraction recovery, and reporting language differ among waters, acid-extractable solids, rare-earth-element work, and phosphorus or sulfur applications.
Draft development sequence
Two environmental suites and two focused extensions.
| Priority | Method | Typical matrix and preparation | Estimated cost per sample* |
|---|---|---|---|
| 1 | TAG-TE01 · Trace elements in waters and dilute extracts | Freshwater, snow or ice melt, permafrost leachates, and approved dilute extracts within verified matrix limits | $24–$30 |
| 2 | TAG-TE3A · Acid-extractable elements in sediments, soils, and particles | Microwave-assisted nitric acid or nitric/hydrochloric-acid extraction; explicitly not a total silicate digestion | $30–$42 |
| 3 | TAG-RE01 · Rare earth elements plus yttrium | Compatible acid extracts and digests; aqueous matrices only after separate verification | $30–$42 |
| 4 | TAG-SP01 · Phosphorus and sulfur | Selected digests and low-matrix aqueous samples | $18–$30 |
*Commissioning estimates, not published prices. The calculation uses a planning rate of $6 per sample-minute. The ranges account for routine instrument acquisition and associated non-sample instrument time. They do not yet include sample preparation, unusual quality-control requirements, method development, or project-specific data interpretation. Final prices will depend on verified methods, batch size, preparation, and tier.
Proposed environmental suites
TAG-TE01
Trace elements in waters and dilute extracts
The focused development panel is derived from EPA Method 200.8: Al, Sb, As, Ba, Be, Cd, Cr, Co, Cu, Pb, Mn, Mo, Ni, Se, Ag, Tl, U, V, and Zn. Mercury is excluded from the initial XR panel because a dedicated mercury workflow is easier to defend. Thorium is reserved for evaluation with TAG-RE01.
Candidate matrices include freshwater, river water, snow or ice melt, permafrost leachates, and approved dilute acid extracts. Filtration, preservation, digestion, turbidity, salinity, and dissolved-solids requirements will be explicit in the verified method. EPA 200.8 informs the scope but does not make TAG-TE01 an EPA-certified compliance method.
TAG-TE3A
Acid-extractable elements in sediments, soils, and particles
The focused panel is derived from the analytes demonstrated for EPA SW-846 Method 6020B: Al, Sb, As, Ba, Be, Cd, Cr, Co, Cu, Fe, Pb, Mn, Ni, Se, Ag, Tl, V, and Zn. Major sodium, potassium, calcium, and magnesium are excluded from the initial XR panel, as is mercury.
Preparation will evaluate microwave-assisted nitric acid or nitric/hydrochloric-acid extraction informed by EPA 3051A. The result is an operationally defined acid-extractable concentration, not a total geochemical concentration; refractory silicates may not be fully recovered.
Focused extensions
TAG-RE01 · REE + Y
The proposed scope is Y and the lanthanide series, with Th and U evaluated as optional additions. Compatible sediment, soil, permafrost, and particle extracts or digests are the initial targets; aqueous matrices require separate verification.
Oxides, hydroxides, and doubly charged rare-earth species require dedicated interference checks and oxide-production monitoring.
TAG-SP01 · P and S
High mass resolution may enable specialized phosphorus and sulfur measurements in selected digests and low-matrix samples. This is a focused elemental method, not a nutrient service competing with established dissolved-nutrient colorimetry.
Resolution strategy
The goal is not to measure every isotope at the highest possible resolution. Higher resolution can reduce sensitivity. Each reportable isotope should use the lowest resolution that demonstrably separates its analyte peak from interferences in the actual matrix.
| Class | Strategy | Illustrative cases |
|---|---|---|
| Clean isotope | Low resolution | Cd, Pb, U, and other relatively clean heavy masses |
| Known polyatomic interference | Medium resolution | Fe, Cr, V, Mn, Co, Ni, and matrix-dependent Cu or Zn |
| Severe or close interference | Medium or high resolution as demonstrated | Difficult As, Se, P, S, or matrix-specific masses |
Development work should use peak scans to establish the position of analyte and interfering species before shortening routine acquisition.
Research areas described in the award
- marine and sea-ice biogeochemistry;
- water quality and environmental contaminants;
- critical minerals and dust inputs;
- paleoceanography and carbon cycling; and
- changing river chemistry in Alaska.
These are examples of research enabled by the acquisition, not a guaranteed analytical menu.
Commissioning path
- Installation and acceptance: verify utilities, safety, instrument performance, and vendor criteria.
- Method development: select target applications, sample introduction, preparation, calibration, and interference controls.
- Local verification: establish precision, bias, blanks, working range, detection capability, and quality-control rules for each method and matrix.
- Pilot access: run limited collaborative samples and improve documentation, data systems, and training.
- Published service: release supported analyses, submission requirements, costs, and realistic turnaround guidance.
Common validation architecture
Every proposed method should address selectivity, calibration, contamination, precision, trueness, recovery, working range, detection and quantitation limits, robustness, carryover, and measurement uncertainty across independent analytical days.
Illustrative run controls
- calibration blank and multi-point calibration;
- second-source verification;
- certified reference material;
- matrix spike and duplicate;
- continuing calibration verification; and
- method, preparation, resin, or column blanks as applicable.
Method record
For each reportable element, the validation summary should connect isotope, resolution, internal standard, calibration and reporting range, detection capability, reference-material performance, within- and between-run precision, recovery, interferences, and decision rules.
Control charts should begin with the first verified batches so empirical warning and control limits can mature with the program.
Batch-based operations
Planning assumes that tuning, mass calibration, standards, blanks, reference materials, periodic checks, rinses, review, and reporting consume substantial time independent of the number of unknowns. Scheduling and future pricing should therefore be based on complete analytical batches and preparation workload—not only nominal minutes per sample.
Project leadership
Principal investigator: Laura Whitmore
Co-investigators: Ana M. Aguilar-Islas and Mette R. Kaufman