Week 12 - Mass Spectrometry

Question 1

Basic principle of Mass Spec

Answer 1

Measure ion acceleration and deflection in response to magnetic or electric fields
mass-to-charge ratio (m/z)

Question 2

Vacuum purpose

Answer 2

Reduces compound fragmentation by preventing ions from colliding with air molecules

Question 3

Procedure for running a non-volatile sample

Answer 3

Small amount of liquid placed in a probe, air locked and heated until evaporated
Should be dissolved in a solvent and allowed to evaporate
Cathode -> Anode

Question 4

Formation of positive ions

Answer 4

Ionization Chamber

Electrons hit the sample, compound loses electrons

Question 5

Parent Ion

Answer 5

Peak at highest mass

lower masses - fragmentation

Question 6

Total Ion Chromatogram

Answer 6

All ions measured

Question 7

Base Peak Chromatogram

Answer 7

Intensity of largest peak in scan

Function of time or scan #

Question 8

Extracted Ion Chromatogram

Answer 8

One ion

Question 9

Electrospray Ionization (ESI)

Answer 9

Liquid phase

Question 10

Atmosphere Pressure Chemical Ionization (APCI)

Answer 10

Gas phase

Question 11

Matrix-Assisted Laser Desorption Ionization (MALDI)

Answer 11

Solid phase