| Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2018) | |
| Biomaterial Surfaces & Interfaces | Tuesday Sessions |
| Session BI-TuM |
| Session: | Bioimaging and Bionanotechnology |
| Presenter: | Paul Blenkinsopp, Ionoptika Ltd, UK |
| Correspondent: | Click to Email |
The emergence of Gas Cluster Ion Beams (GCIB) for SIMS has significantly extended the available mass range of the technique, and in so doing has also widened the scope of its applications. The low-damage nature of GCIB sputtering greatly improves yields of higher mass molecular species, however spatial resolution remains a challenge. Of particular interest is the ability to detect and image intact bio-molecules in tissue and cells at spatial resolutions below 1 micron. Here, we present on the latest advancements in gas cluster beam technology for ToF SIMS, demonstrating significant progress towards these goals.
We report on the results of our latest innovation – a 70kV Gas Cluster Ion Beam, the GCIB SM. Most current GCIB sources operate at energies between 10 and 40kV, however there are several theoretical benefits to extending the energy range beyond this, including improved focusing and greater secondary ion yields. With the GCIB SM, we demonstrate both a reduction in spot size – improving the resolving power by a factor of 3 – as well as an increase in total current – which has benefits for both speed of analysis, as well as for greater depth profiling capabilities.
We also present on methods to increase ion yields of high-mass species by utilizing alternative source gases to argon. We demonstrate that by choosing an appropriate source gas, yield enhancements greater than 10 times can be achieved. As analysis volumes decrease with greater resolving power, techniques such as this are expected to play a vital role in obtaining the highest quality imaging SIMS data. These latest developments are now enabling SIMS imaging of species such as lipids and gangliosides in tissue at resolutions greater than 2 microns.