X-ray holograms at improved resolution: a study of zymogen granules.
X-ray holography offers the possibility of three-dimensional microscopy with resolution higher than that of the light microscope and with contrast based on x-ray edges. In principle, the method is especially advantageous for biological samples if x-rays in the wavelength region between the carbon and oxygen K edges are used. However, until now the achieved resolution has not exceeded that of the light microscope because of the poor coherence properties of the x-ray sources and the low resolution of the detectors that were available. With a recently developed x-ray source based on an undulator on an electron storage ring, and high resolution x-ray resist, a hologram has been recorded at about 400-angstrom resolution. The experiment utilized x-rays with wavelengths of 24.7 angstroms and required a 1-hour exposure of the pancreatic zymogen granules under study.
Howells
M
M
Center for X-ray Optics, Lawrence Berkeley Laboratory, University of California, Berkeley 94720.
Jacobsen
C
C
Kirz
J
J
Feder
R
R
McQuaid
K
K
Rothman
S
S
D000818:Animals; D003594:Cytoplasmic Granules / Q000201:enzymology / Q000648:ultrastructure*; D004792:Enzyme Precursors; D006696:Holography / Q000379:methods*; D008854:Microscopy, Electron; D010179:Pancreas / Q000648:ultrastructure; D051381:Rats; D014965:X-Rays
D004792:Enzyme Precursors