An in situ fracture device to image lipids in single cells using ToF-SIMS

• Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) imaging yields molecule-specific images showing the spatial distribution of specific lipids with submicron resolution, making it a potentially powerful method for studying a variety of biological questions in single cells. In order to make possible the analysis of hydrated cells in vacuum, we have designed a device for in situ freeze-fracture of cell samples. PC12 cells are frozen between two silicon shards in a sandwich geometry, and the fracture is conducted under vacuum inside the analysis chamber of the instrument. After freeze-fracture, ToF-SIMS analysis was carried out using a Bi cluster ion source, providing high-resolution images of single cells. We also show that when combining freeze-fracture and cluster SIMS imaging, low abundant biologically important lipids, specifically PE, PC and non-SM PC, can be imaged in single cells. Finally, K+ ion localization was used as a diagnostic to identify fracture planes through the cell for these fractured samples.

Subject headings

NATURVETENSKAP  -- Kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences (hsv//eng)

Keyword

tof-sims imaging

pc12 cells

freeze-fracture

phospholipids

pc12 cells

Publication and Content Type

ref (subject category)

art (subject category)