A fast, free, and open-source desktop application for single-particle ICP-ToF-MS data analysis
| Platform | Requirements | Download |
|---|---|---|
| macOS — Apple Silicon | macOS 11.0 (Big Sur) or later · 4 GB RAM (8 GB recommended) | IsotopeTrack_M.dmg |
| Windows | Windows 10 (64-bit) or later · 4 GB RAM (8 GB recommended) | IsotopeTrack_Setup_W.exe |
- Multi-isotope single-particle detection across all measured elements simultaneously
- Three detection methods — Compound Poisson Log-Normal and Manual threshold
- Transport rate calibration — mass-based, number-based, and weighted liquid methods
- Ionic calibration — automatic model selection (Simple Linear, Linear with intercept, Weighted Linear)
- 16 result plot types on a drag-and-drop canvas — bar charts, heatmaps, correlation, clustering, isotope ratios, triangle plots, network graphs, and more
- Supports Nu Vitesse folders (
run.info), TOFWERK (.h5), and CSV formats - Built-in materials database with mass fraction and density lookup
- Batch processing and CSV export
Click Import Data in the File menu or sidebar. Load all samples you plan to analyze in a single session to ensure consistent processing parameters.
Use the periodic table interface to select the isotopes of interest. Selected isotopes are carried automatically into all calibration panels.
Configure ionic calibration to convert raw counts to mass. Use -1 to exclude samples from specific calibration sets. IsotopeTrack evaluates three calibration models and automatically selects the best R². Manual override is available.
Calibrate aerosol transport efficiency using one of three methods: mass-based, number-based, or weighted liquid. Average multiple measurements or select the most reliable single value.
For each sample, specify the mass fraction of the target element and the particle density from the built-in materials database.
Configure detection method, confidence level, minimum peak points, and optional smoothing for each element individually or via Batch Edit Parameters.
Use the drag-and-drop results canvas to visualize and validate the analysis. Add plot nodes, adjust parameters, and explore multi-element relationships interactively.
Export a summary file (all samples and elements, statistics, concentrations, calibration info) and/or a details file (individual particle data per sample).
- Folder with
run.info— Raw data from Nu Vitesse instruments - TOFWERK
.h5— HDF5 acquisition files - CSV files — Time-series data
- First column must be Time (units:
ms,ns, ors) - Each element column must include mass number + element symbol (e.g.,
107Ag,56Fe) - Data must be provided in counts
Example datasets for trying out IsotopeTrack (ionic calibration sets, transport efficiency standards, and multi-element nanoparticle samples) are available as zip files in the example-data release. Download, unzip, and import via File → Import Data.
| Method | Description |
|---|---|
| Compound Poisson Log-Normal | Advanced method accounting for signal distribution characteristics |
| Manual | User-defined threshold value |
Statistical summaries (mean, median, standard deviation), particle concentrations, size distributions, calibration information and method parameters for all samples and elements.
Individual particle data for each sample with complete particle-by-particle information, peak characteristics, and integration results.
If you use IsotopeTrack in your research, please cite:
Ahabchane H, Goodman A, Hadioui M, Wilkinson K. IsotopeTrack: A fast and flexible application for the analysis of SP-ICP-TOF-MS datasets. Environmental Chemistry 2026; EN25111. https://doi.org/10.1071/EN25111
IsotopeTrack builds upon the work of the spICP-MS community. We are deeply grateful to all scientists whose published methodologies, open-source tools, and foundational research form the scientific backbone of this software.
We particularly acknowledge SPCal, developed by T. E. Lockwood, R. Gonzalez de Vega, L. Schlatt, and D. Clases. Certain algorithmic approaches and detection methods implemented in IsotopeTrack were informed by their work.
Lockwood, T. E., Gonzalez de Vega, R., & Clases, D. (2021). An interactive Python-based data processing platform for single particle and single cell ICP-MS. Journal of Analytical Atomic Spectrometry, 36(11), 2536–2544. https://doi.org/10.1039/D1JA00297J
Lockwood, T. E., Schlatt, L., & Clases, D. (2025). SPCal – an open source, easy-to-use processing platform for ICP-TOFMS-based single event data. Journal of Analytical Atomic Spectrometry. https://doi.org/10.1039/d4ja00241e
Compound Poisson signal distribution models:
Hendriks, L., Gundlach-Graham, A., & Günther, D. (2019). Performance of sp-ICP-TOFMS with signal distributions fitted to a compound Poisson model. Journal of Analytical Atomic Spectrometry. https://doi.org/10.1039/c9ja00186g
Gundlach-Graham, A., et al. (2018). Monte Carlo Simulation of Low-Count Signals in Time-of-Flight Mass Spectrometry and Its Application to Single-Particle Detection. Analytical Chemistry, 90(20), 11847–11855. https://doi.org/10.1021/acs.analchem.8b01551
Transport rate reference:
Pace, H. E., et al. (2011). Determining transport efficiency for the purpose of counting and sizing nanoparticles via single-particle ICP-MS. Analytical Chemistry, 83, 9361–9369. https://doi.org/10.1021/ac201952t
IsotopeTrack is free and open-source software released under the GNU General Public License v3.0.