seperation techniques 1

Question 1

why do you need to prepare before seperation?

Answer 1

• prepare substance to study or for commercial use

Question 2

what is determination?

Answer 2

• qualifying a substance in a biological sample. includes qualification and quantification

Question 3

what is separation with dialysis

Answer 3

• based on commercial membranes with pores of pre- determined size
• unit = molecular weight cut off
• removes all molecules/ ions = so good for desalting
  but SLOW AND LABOROUS

Question 4

what are dialysis membranes made of?

Answer 4

• cellophane
• cellulose nitrate
• various plastics

Question 5

what is filtrate and retentate?

Answer 5

filtrate = what goes through
retentate = what stays behind

Question 6

CONDITIONS FOR ROLL OF VISKING TUBING?

Answer 6

must be hydrated and pre- treated before use to remove contaminants

Question 7

what is ultrafiltration?

Answer 7

• similar membranes are filled with protein solutions and then a force is applied to force the proteins and water through the membrane.

Question 8

what is central ultrafiltration?

Answer 8

• uses centrifuge to apply force to the solution - pulling it through

Question 9

in centrifuge what is pulled through?

Answer 9

• water, salts, and everything below MWCO

Question 10

what is pressure ultrafiltration?

Answer 10

• same as centrifuge
• uses chamber where base is filter and top connected to cylinder of argon gas
• gas pressure above the liquid pushes it throught the filter

Question 11

what is chromotography?

Answer 11

• useful fro any type of biological molecule
• can be used to seperate on the basis of shape, size, ionisation, polarity, hydrophobicity

Question 12

what is chromatography theory

Answer 12

• solution of solutes dissolved in solvent

Question 13

what is stationary phase?

Answer 13

eg. paper, silica gel, waxy beads, plastic beads

Question 14

what is mobile phase?

Answer 14

• buffer solutions, helium, nitrogen, organic solvents

Question 15

chromatography paper

Answer 15

• paper is cheaper,
• but slower

Question 16

chromatography TLC

Answer 16

• faster
• expensive

Question 17

what does iodine vapour detect?

Answer 17

• unsaturated fatty acids as brown spots

Question 18

what does ninhydrin detect?

Answer 18

• amino acids - most are violet, but some yellow, brown

Question 19

what does sulfuric acid detect?

Answer 19

• triglycerides and cholesterol (brown/ black)

Question 20

what does m- phenylene diamine with stannous chloride detect?

Answer 20

• sugars as dark violet

Question 21

what does bromocresol green detect?

Answer 21

• acidic components (yellow) and basic components (blue) on a green field
• useful for carboxylic acids and amines

Question 22

what does silver nitrate in acetone detect?

Answer 22

• inorganic sulfur compounds as brown spots on yellow field

Question 23

what does rhodamine B detect?

Answer 23

• phospholipids

Question 24

how to add efficiency to chromatography?

Answer 24

1. plates/ paper inefficient
2. column chromatography allows automation of the process.
3. using liquid chromatography
4. use FPLC and HPLC

Question 25

basics of FPLC?