Identification of cellular sections with imaging mass spectrometry following freeze fracture.
Anal Chem
; 74(16): 4020-6, 2002 Aug 15.
Article
in En
| MEDLINE
| ID: mdl-12199569
ABSTRACT
Freeze-fracture techniques have been used to maintain chemical heterogeneity of frozen-hydrated mammalian cells for static TOF-SIMS imaging. The effects the fracture plane has on scanning electron microscopy and dynamic SIMS images of cells have been studied, but the implications this preparation method has on static SIMS have not been addressed to date. Interestingly, the chemical specificity and surface sensitivity of TOF-SIMS have allowed the identification of unique sections of rat pheochromocytoma cells exposed to the sample surface during freeze fracture. Using the extensive chemical information of the fractured surface, cellular sections have been determined using TOF-SIMS images of water, sodium, potassium, hydrocarbons, phosphocholine, and DiI, a fluorescent dye that remains in the outer leaflet of the cell membrane. Higher amounts of potassium have been imaged inside a cell versus the surrounding matrix in a cross-fractured cell. In other fractures exposing the cell membrane, phosphocholine and DiI have been imaged on the outer leaflet of the cell membrane, while phosphocholine alone has been imaged on the inner leaflet. In this paper, we discuss how imaging mass spectrometry isused to uniquely distinguish three possible sections of cells obtained during freeze fracture. The identification of these sections is important in choosing cells with a region of interest, like the cell membrane, exposed to the surface for a more thorough investigation with imaging static TOF-SIMS.
Search on Google
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Diagnostic Imaging
/
Cytological Techniques
/
Spectrometry, Mass, Secondary Ion
/
Freeze Fracturing
Type of study:
Diagnostic_studies
Limits:
Animals
Language:
En
Journal:
Anal Chem
Year:
2002
Document type:
Article
Affiliation country:
Estados Unidos