Chromatography

Question 1

chromatography

Answer 1

separation of individual constituents of a mixture based on physical differences

Question 2

physical differences

Answer 2

adsorption
charge
size
biological specificity

Question 3

Thin Layer Chromatography

Answer 3

• thin, uniform silica gel coated on plastic plate
• stationary phase: silica gel
• mobile phase: suitable solvent
• used to separate lipids from red blood cells

Question 4

Rf

Answer 4

retention factor

= distance moved by substance x / distance moved by solvent front y

Question 5

Gel Filtration (size exclusion)

Answer 5

• uses gel with porous beads to separate substances according to molecular size
• small molecules move slower
• large molecules move faster
• elution fraction determines Mw

Question 6

Sephadex

Answer 6

bead-formed dextran gel
hydrophilic
swells in water

Question 7

Ion exchange

Answer 7

• separates proteins on basis of charge
• used to separate oxidised and reduced species of cyt c
• exchanger used depends on net charge of protein under consideration at a particular pH
• proteins eluted by changes in pH or ionic strength of chromatography buffer

Question 8

DEAE

Answer 8

anion exchanger with mobile exchangeable counter anions

Question 9

CM

Answer 9

cation exchanger with mobile exchangeable counter cations

Question 10

Affinity Chromatography

Answer 10

• purifies biological molecules based on biological specificity
• isolation of protein on bioligand immobilised inert matrix
• used to assay for LDH activity