Microscopía Electrónica y Confocal

Scanning Electron Microscopy

Aaron O'Dea

ZEISS EVO 40 VP scanning electron microscope.

Detectors:

  1. Secondary electron detector (SED).
  2. Quad backscatter electron detector (QBSED).
  3. Variable pressure secondary electron detector (VPSE).

Observations

  1. Observation of specimens in high vacuum with secondary and backscattered electron detector (ES/BSE).
  2. Observation of specimens at variable pressure with secondary and backscattered electron detector (ES/BSE).
  3. Observation of fresh biological material without the need for metallic coating or the use of fixers, thereby decreasing the risk of contamination and the possible presence of artifacts in the specimen.
  4. Observation of ultrathin slices with electrons transmitted through the STEM system (Scanning Transmission Electron Microscopy).
  5. Use of cold mount, which permits the observation of fresh specimens.

Other facilities:

Critical point drying: using a Denton Vacuum DCP-1 critical point dryer (Critical Point Drying Apparatus C P D-1), very fragile specimens can be dried which would otherwise be deformed by oven or air drying.

Metallic coating: an Anatech Hummer VI-A ( Hummer VI-A Sputtering System) metallic coater is used on specimens which need to be observed in high vacuum. In this process, specimens are coated with a thin layer of gold/palladium (60%:40%) to make them conductive to the passage of secondary electrons.