Secondary Ion Mass Spectrometry (SIMS)

The new Hybrid SIMS enables surface characterisation with OrbiTrap mass resolution

ToF-SIMS at a glance

Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) is a highly sensitive analytical technique that describes the chemical composition and distribution of a sample surface. It uses a range of incident ion sources to impact on solid surfaces and generate secondary ions that can be analysed by a time of flight (or Orbitrap) mass spectrometer to determine the surface chemistry of that surface or layer.

Applications

Surface Spectrometry
Surface Chemical Imaging
Depth Profiling

ToF-SIMS analysis uses specialised ion beams in an ultra high vacuum system

How does ToF-SIMS work?

ToF-SIMS uses a pulsed primary ion beam (Bi_n+, Cs+, Ar+, etc.) to impact on a sample surface and induce a fragmentation cascade. The result is the desorption of neutrals, secondary ions (+/-) and electrons from the first few monolayers of the sample. The secondary ions can then be accelerated into a "flight tube" and their mass is determined by measuring the exact time at which they reach the detector (i.e. time-of-flight).

A single secondary ion mass spectrum can be used to describe the constituents of one point on a surface. Alternatively if the incident beam is rastered across several points within a given surface area, it is possible to build a chemical image map of that surface. Using incident ions such as Cs+, Ar_n+ C60+ in a dual beam approach it is also possible to sputter through the top layers of the inorganic or organic surfaces respectively while monitoring the incidence profile of elemental or molecular species (i.e. depth profiling).

ISAC ToF-SIMS facilites offer multiple ion sources and operational modes to suit the desired application

A look inside the chamber of the Ion-TOF IV

Understanding surface and interface science. Making our expertise count.

Our ToF-SIMS facilities

ION-TOF (GmBH) ToF SIMS V

Liquid metal (Bin+n) ion gun (LMIG) for spectroscopy and imaging at a spatial resolution of ~ 200 nm.
Argon gas cluster source for the high resolution depth profiling of organic materials (polymers and biological samples) and 3D chemical characterisation.
Sensitivity down to ppm (femtomole).
A 5-axis multi-sample stage is fully automated and provides rotation for high resolution (nm) depth profiling (Cs+ or Ar gas cluster ion beam sources).
Reflectron ToF mass analyser gives mass resolution > 13000 at m/z = 29.
Image surface areas from the µm to cm scale.
3-D elemental mapping possible.
Wide range of samples accepted including conductors, semi-conductors and insulators.
Powders, foils, biological materials etc.
Sample size ranging from a few mm up to ~ 10 cm.

ION-TOF (GmBH) Hybrid SIMS ("3D-OrbiSIMS")

Hybrid SIMS system combining ToF-SIMS with an Orbitrap mass spectrometer.
The first of its kind in an academic setting the instrument combines the function of the two hybridised components to facilitate an unprecedented level of mass spectral molecular analysis for a range of materials (hard and soft matter, biological cells and tissues).
The dual functionality underpins spatial and mass resolution improvements in chemical identification and imaging.
Allows state-of-the-art ToF-SIMS using the ToF V chassis independent or in combination with unparalleled mass resolution from the Orbitrap detector.
Ideal for identifying and mapping unknown organic species in complex solid samples (tissues, cells etc.)
High mass resolution spectrometry (>240,000 and 11,000 amu for the OrbiTrap and the ToF, respectively).
High spatial resolution chemical imaging (<70 nm).
Cryogenic sample preparation facility, including high pressure freezing, freeze drying, cryo-ultramicrotomy and cryogenic transfer system.
Category 2 preparation facilities for cell/tissue analysis and sample transfer to correlative techniques (cryo-SEM, cryo-TEM, cryo-microscopy etc.)

Publications of interest - ToF-SIMS

A Reactive Prodrug Ink Formulation Strategy for Inkjet 3D Printing of Controlled Release Dosage Forms and Implants, He, Y., Foralosso, R., Trindade, G. F., Ilchev, A., Ruiz-Cantu, L., Clark, E. A., Khaled, S., Hague, R. J. M., Tuck, C. J., Rose, F. R. A. J., Mantovani, G., Irvine, D. J., Roberts, C. J. & Wildman, R. D., Advanced Therapeutics, 3, 1900187 (2020).
High sensitivity analysis of nanogram quantities of glycosaminoglycans using ToF-SIMS, Hook, A. L., Hogwood, J., Gray, E., Mulloy, B. & Merry, C. L. R., Communications Chemistry, 4, 67 (2021).
Residual polymer stabiliser causes anisotropic electrical conductivity during inkjet printing of metal nanoparticles, Wang, F., Im, J., He, Y., Balogh, A., Scurr, D., Gilmore, I., Tiddia, M., Saleh, E., Pervan, D., Turyanska, L., Tuck, C. J., Wildman, R., Hague, R. & Roberts, C. J., Communications Materials, 2, 47 (2021).
Imaging mass spectrometry of fingermarks on brass bullet casings using sample rotation, Lee C. J., Scurr, D. J., Jiang, L., Kenton, A., Beebe, S. R. T. & Sharp, J. S., Analyst, 146, 7563–7572 (2021).
A new particle mounting method for surface analysis, Dundas, A., Kern, S., Cuzzucoli Crucitti, V., Scurr, D. J., Wildman, R., Irvine, D. J. & Alexander, M. R., Surface and Interface Analysis, 54, 374–380 (2022).
The influence of printing parameters on multi-material two-photon polymerisation based micro additive manufacturing, Hu, Q., Rance, G. A., Trindade, G. F., Pervan, D., Jiang, L., Foerster, A., Turyanska, L., Tuck, C., Irvine, D. J., Hague, R. & Wildman, R. D., Additive Manufacturing, 51, 102575 (2022).

Publications of interest - 3D OrbiSIMS

Protein identification by 3D OrbiSIMS to facilitate in situ imaging and depth profiling, Kotowska, A. M., Trindade, G. F., Mendes, P. M., Williams, P. M., Aylott, J. W., Shard, A. G., Alexander, M. R. & Scurr, D. J. Nature Communications,11, 5832 (2020).
Spatially Resolved Molecular Compositions of Insoluble Multilayer Deposits Responsible for Increased Pollution from Internal Combustion Engines, Edney, M., Lamb, J., Spanu, M., Smith, E., Steer, E., Wilmot, E., Reid, J., Barker, J., Alexander, M., Snape, C. & Scurr, D., ACS Applied Materials & Interfaces,12, 51026–51035 (2020).
Cryo-OrbiSIMS for 3D Molecular Imaging of a Bacterial Biofilm in Its Native State, Zhang, J., Brown, J., Scurr, D. J., Bullen, A., MacLellan-Gibson, K., Williams, P., Alexander, M. R., Hardie, K. R., Gilmore, I. S. & Rakowska, P. D., Analytical Chemistry,92, 9008–9015 (2020).
Sequential Orbitrap Secondary Ion Mass Spectrometry and Liquid Extraction Surface Analysis-Tandem Mass Spectrometry-Based Metabolomics for Prediction of Brain Tumor Relapse from Sample-Limited Primary Tissue Archives, Meurs, J., Scurr, D. J., Lourdusamy, A., Storer, L. C. D., Grundy, R. G., Alexander, M. R., Rahman, R. & Kim, D.-H., Analytical Chemistry, 93, 6947–6954 (2021).
Molecular Formula Prediction for Chemical Filtering of 3D OrbiSIMS Datasets, Edney, M. K., Kotowska, A. M., Spanu, M., Trindade, G. F., Wilmot, E., Reid, J., Barker, J., Aylott, J. W., Shard, A. G., Alexander, M. R., Snape, C. E. & Scurr, D. J., Analytical Chemistry, 94, 4703–4711 (2022).
Elucidating the molecular landscape of the stratum corneum, Starr, N. J., Khan, M. H., Edney, M. K., Trindade, G. F., Kern, S., Pirkl, A., Kleine-Boymann, M., Elms, C., O’Mahony, M. M., Bell, M., Alexander, M. R. & Scurr, D. J., Proceedings of the National Academy of Sciences, 119, e2114380119 (2022).