Comparison of C_(60) and GCIB primary ion beams for the analysis of cancer cells and tumour sections (Conference Paper)

摘要

We have implemented a gas cluster ion beam (GCIB) system developed by Ionoptika Ltd (Southampton, UK) with sufficient control to allow us to exploit the unique capabilities of our J105 instrument for imaging and depth profiling. The J105 allows us to use the GCIB as continuous primary ion beam, thereby overcoming the issues associated with pulsing these slow moving, mixed species beams. We have performed a direct comparison with C_(60) ions on the same samples in the same instrument. The GCIB beams are more difficult to focus than the C_(60) ~+ ion beam, making single-cell imaging difficult, although spot sizes of 15-20 μm are readily obtainable for Ar _(1000) and Ar_(2000), providing good resolution for larger area imaging on tissue section/biopsy samples. In this paper, we present results from the assessment of these new beams as primary ions for the analysis of 'real', complex biological systems. Initial spectra and those following increased primary ion bombardment were compared for in vitro cultured cells deposited on silicon and cryo-sectioned tumour samples originating in vivo. Ar_(1000) ~+ and Ar_(2000) ~+ showed increased persistence of the signals from intact molecular ions of phospholipids and a reduction in the accumulation of chemical background noise compared with C _(60) ~+ analysis.