Adv. Techniques in Microscopy Flashcards
Give 5 examples of light microscopy
Bright-field, Phase Contrast, Differential Interference Contrast, Fluorescence, Confocal Laser/Fluorescence
Give the 2 types of electron microscopes
Transmission and Scanning
What are light microscopes good for examining?
Tissue specimens
What are the advantages of digital microscopes?
Very high resolution, use a low heat light source so good for examining living cells
When is phase contrast microscopy used?
Used when specimens appear transparent when bright-field illumination is used. Can be used to examine dynamic events in living cells
Who invented differential interference contrast microscopy?
Nomarski
Give 2 examples of fluorescent dyes
Fluorescein (green emission), Rhodamine (red emission)
Explain immunofluorescence microscopy
Uses antibodies linked to a fluorescent dye to detect specific proteins in a cell
What is a ‘vital’ fluorescent dye used for? Give an example
For staining (parts of) living cells. FM 4-64, a hydrophobic dye that only stains membranes`
What is a GFP?
A Green Fluorescent Protein is a protein that fluoresces under UV light excitation
What is FRET?
Förster/Fluorescence Resonance Energy Transfer. Based on GFP technology.
What is Confocal Laser/Fluorescence used for?
Used for examining a transection through the sample
What is the resolution of TEM?
Can be as low as 0.1nm
For TEM, what kind of material is used for staining the sample?
Electron dense materials eg gold, osmium
What is immunoelectron microscopy?
Where gold particles are attached to antibodies to detect specific particles
What is the resolution of SEM?
~10nm
What is the resolution of SEM?
~10nm
What is TEM used for?
Examining the fine structure of organelles
What is SEM used for?
Examining the surface topography
For SEM, what kind of material is used for staining the sample?
A heavy metal eg platinum
What is ESEM?
Environmental SEM. A SEM that allows a gaseous environment in the specimen chamber, meaning live specimens can be examined. All other electron microscopes operate in a vacuum.
