Exam 1- Lecture 9

Question 1

How does liquid chromatography work

Answer 1

liquid sample separated by reverse phase chromatography

Question 2

What is tandem mass spectrometry

Answer 2

technique where two or more mass analyzers are coupled together
selection and sequential fragmentation of primary ions into additional ions

Question 3

What is the application of MS/MS

Answer 3

fragmenting peptides into component amino acid masses

Question 4

What is MALDI-MS

Answer 4

matrix assisted laser desportion/ionization mass spectrometry

Question 5

How does MALDI work

Answer 5

sample spotted on substrate with matrix that assists ionization

Question 6

What is gas chromatography

Answer 6

components of a sample are dissolved in a solvent and vaporized in order to separate the analytes by disturbing the sample between two phases: stationary and mobile phase

Question 7

What is electrospray ionization

Answer 7

peptides dissolved in liquid, very small droplets are released from a narrow capillary tube

Question 8

What is MALDI

Answer 8

matrix assisted laser desorption ionization
peptides embedded in a material such as 4-methoxycinnamic acid that absorbs laser light

Question 9

How does MALDI work

Answer 9

matrix absorbs and transfers energy to peptides, peptides releases different ions, ions accelerated through vacuum tube and mass is calculated

Question 10

What is TOF

Answer 10

used to record intensity and calculates the mass
measurement of time taken by particle to travel a distance through medium

Question 11

What is the function of quadrupole ion traps

Answer 11

capture ions in electric field
ejected by into detector by second electric field

Question 12

What is ion mobility sepectrometry

Answer 12

separates gas phase ions based on their interactions with a collision gas and their masses

Question 13

What is a faraday cup

Answer 13

metal conductive cup designed to catch charged particles in vaccum

Question 14

What is an electron multiplier

Answer 14

vacuum tube structure that multiplies incident charges

Question 15

What is an obitrap

Answer 15

ion trap mass analyzer with outer barrel like electrode and coaxial inner spindle like electrode that traps ions in orbital motion

Question 16

What is ion cyclotron resonance?

Answer 16

uses a superconducting magnet to trap ions in a small sample cell

Question 17

What is required for MS/MS

Answer 17

collision cell

Question 18

what are the types of ionization

Answer 18

ESI
MALDI

Question 19

what are the types of mass analyzers

Answer 19

quadrupole
ion mobility separation

Question 20

what are the types of detectors

Answer 20

faraday cup
electron multipliers
TOF
obitrap
ICR

Question 21

What is liquid chromatography

Answer 21

method of physical separation in which components of a liquid mixture are distributed between to immiscible phases

Question 22

in LC, components within a mixture are separated in a column based on each components affinity for the

Answer 22

mobile phase

Question 23

What is gas chromatography

Answer 23

components of sample are dissolved in a solvent and vaporized in order to separate the analytes by distributing the sample between mobile and stationary phase

Question 24

What is the mobile phase

Answer 24

chemically inert gas that serves to carry the molecules of the analyte through the heated colum