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Preparation of Prokaryotic and Eukaryotic Organisms Using Chemical Drying for Morphological Analysis in Scanning Electron Microscopy (SEM)
Published on: January 7, 2019
A simple and rapid scanning electron microscope preparative technique for delicate "gymnodinioid" dinoflagellates
Lizeth Botes1, Brendon Price, Miranda Waldron
1Marine and Coastal Management, Rogge Bay, Cape Town, 8012, South Africa. LBOTES@MCM.WCAPE.GOV.ZA
Microscopy Research and Technique
|October 10, 2002
Summary
Scanning electron microscopy (SEM) effectively visualizes delicate dinoflagellates using poly-L-lysine and hexamethyldisilazane (HMDS). This method overcomes cell distortion, offering a simpler, cheaper alternative to critical point drying (CPD).
Area of Science:
- Marine Biology
- Microscopy
- Protistology
Background:
- Light microscopy (LM) struggles to resolve fine details in delicate "gymnodinioid" dinoflagellates.
- Essential morphological features like apical grooves and pores are often obscured at LM resolution.
Purpose of the Study:
- To develop an improved scanning electron microscopy (SEM) protocol for delicate "gymnodinioid" dinoflagellates.
- To overcome cell distortion issues common with traditional SEM preparation methods.
Main Methods:
- Cells were fixed with osmium tetroxide (OsO4).
- Cells were adhered to glass coverslips using poly-L-lysine.
- Cells were dehydrated through an ethanol series.
- Cells were dried using hexamethyldisilazane (HMDS) as a substitute for critical point drying (CPD).
Main Results:
- The combined poly-L-lysine and HMDS protocol effectively prevented cell shrinking and collapsing.
- SEM imaging revealed clear morphological details of the dinoflagellate theca.
- The method proved successful for unarmoured and lightly armoured gymnodinioid species.
Conclusions:
- The poly-L-lysine and HMDS method offers a cost-effective, time-efficient, and accessible SEM preparation technique.
- This protocol significantly enhances the study of delicate dinoflagellate morphology.
- It provides a viable alternative to CPD, requiring less specialized equipment and expertise.
