Lecture 8 : Fluorescence Flashcards
1
Q
What is fluorescence
A
When a substance absorbs light then reemits it imeediately, more sensitive than absorption.
Emission intensity directly proportional to excitation intensity
2
Q
What are fluorophores
A
Materials with fluorescent properties, dyes or stains, some natural, some designed.
Fluorophores always absorb light at shorter wavelength and emit at longer wavelength, specific to each fluorophore
3
Q
What is the stokes shift
A
Difference between absorption and emission on graph
4
Q
Measuring Fluorescence
A
5
Q
Example
A
6
Q
What are intrinsic fluorophores
A
natural, proteins and peptides
7
Q
What are extrinsic fluorphores
A
Labelling / tagging a fluorophore onto a sample
8
Q
What are calcium chelators
A
- Helps visualise changes in calcium levels in cells
9
Q
What is the importance of solvent
A
- More protonated molecule, more fluorescent
- So polar fluorophores are more sensitive to solvent polarity
10
Q
What is the effect of pH
A
