FAAS and GFAAS basics

Question 1

How does FAAS Work?

Answer 1

Air/acetylene or NO2/acetylene flame used to evaporate solvent and dissociate sample into component atoms. When atoms pass through flame they absorb light from flame and this is recorded by the detector which is then analysed to provide a concentration.

Question 2

Schematic of FAAS?

Answer 2

LAMP -> FLAME SAMPLE -> MONOCHROMATOR -> DETECTOR

Question 3

Strengths and weaknesses of FAAS?

Answer 3

Strengths:
Easy fast and cheap
low interferences
good performance

Weaknesses:
moderate LOD
Element limitations
1-10 elements per analysis

Question 4

How does GFAAS work?

Answer 4

Very similar to FAAS but uses a graphite furnace rather than a flame

Question 5

Schematic of GFAAS?

Answer 5

LAMP -> CUVETTE (GRAPHITE FURNACE) -> MONOCHROMATOR -> DETECTOR

Question 6

Strengths and Weaknesses of GFAAS?

Answer 6

Strengths:
Good LOD
Can have very little sample
low SPECTRAL interference

Weaknesses:
Slower
Element Limitations
Chemical interferences