Ch 4

Question 1

the migration of charged solutes or particles in an electrical field.

Answer 1

Electrophoresis

Question 2

refers to the migration of small ions

Answer 2

Iontophoresis

Question 3

is the migration of charged macromolecules in a porous support medium such as paper, cellulose acetate, or agarose gel film

Answer 3

Zone Electrophoresis

Question 4

film is soaked in buffer, the air spaces fill with electrolyte and the film becomes pliable.

Answer 4

Cellulose acetate

Question 5

another widely used supporting medium. Used as a purified fraction of agar, it is neutral and, therefore, does not produce electroendosmosis

Answer 5

Agarose Gel

Question 6

-involves separation of protein on the basis of charge and molecular size. Separates serum proteins into 20 or more fractions rather than the usual 6 fractions separated by cellulose acetate or agarose. It is widely used to study individual proteins

Answer 6

Polyacrylamide Gel

Question 7

separates proteins on the basis of surface charge and molecular size, as does polyacrylamide gel. The procedure is not widely used because of technical difficulty in preparing the gel.

Answer 7

Starch gel

Question 8

The movement of buffer ions and solvent relative to the fixed support is called

Answer 8

Endosmosis or Electroendosmosis

Question 9

Charged proteins migrate through a support medium that has a continuous pH gradient.

Answer 9

Isoelectric focusing

Question 10

is used in the clinical laboratory to characterize monoclonal proteins in
serum, urine, or cerebrospinal fluid (CSF).

Answer 10

Immunofixation electrophoresis

Question 11

separation is performed in narrow-bore, fused silica capillaries (inner diameter 25 to 75 um).

Answer 11

Capillary electrophoresis

Question 12

is the bulk flow of liquid toward the cathode upon application of an electric field, and it is superimposed on electrophoretic migration

Answer 12

Electroosmotic Flow (EOF)

Question 13

This electrophoresis assay combines two different electrophoresis dimensions to separate proteins from complex matrices such as serum or tissue.

Answer 13

Two-Dimensional Electrophoresis

Question 14

is the principle of measuring the concentration of solute particles in a solution using one of the four colligative properties discussed below

Answer 14

Osmometry

Question 15

enables the study of the binding of ligands to surface receptors such as membrane proteins in real time.

Answer 15

Surface plasmon resonance

Question 16

a similar label-free technique that uses sensor tips instead of a flat metal surface.

Answer 16

Biolayer interferometry

Question 17

refers to the group of techniques used to separate complex mixtures on the basis of different physical interactions between the individual compounds and the stationary phase of the system

Answer 17

Chromatography

Question 18

also known as liquid- solid chromatography, is based on the competition between the sample and the mobile phase for adsorption sites on the solid stationary phase.

Answer 18

Adsorption

Question 19

also referred to as liquid- liquid chromatography. Separation of solute is based on relative solubility in an organic (nonpolar) solvent and an aqueous (polar) solvent. In its simplest form, it is performed in a separatory funnel

Answer 19

Partition

Question 20

a variation of liquid-solid chromatography, is used to separate solute molecules on the basis of size and shape. The chromatographic column is packed with porous material

Answer 20

Steric exclusion

Question 21

used to remove interfering substances from a solution, to concentrate dilute ion solutions, and to separate mixtures of charged molecules, such as amino acids. Changing pH and ionic concentration of the mobile phase allows

Answer 21

Ion exchange chromatography

Question 22

a variant of column chromatography. A thin layer of sorbent, such as alumina, silica gel, cellulose, or cross-linked dextran, is uniformly coated on a glass or plastic plate.

It is most commonly used as a semiquantitative screening test.

Answer 22

Thin-Layer Chromatography

Question 23

uses pressure for fast separations, controlled temperature, inline detectors, and gradient elution techniques.

Answer 23

High Performance Liquid Chromatography (HPLC)

Question 24

forces the mobile phase through the column at a much greater velocity than that accomplished by gravity flow columns and includes pneumatic, syringe, reciprocating, or hydraulic amplifier pumps.

Answer 24

Pumps

Question 25

The most common material used for column packing

Answer 25

Silica gel

Question 26

used to separate mixtures of compounds that are volatile or can be made volatile.

Answer 26

Gas chromatography

Question 27

The column effluent is fed into a small hydrogen flame burning in excess air or atmospheric oxygen.

Answer 27

Flame ionization detectors

Question 28

The most common form of ionization used in GC/MS. This method requires a source of electrons in the form of a filament to which an electric potential is applied, typically at 70 eV.

Answer 28

Electron ionization

Question 29

ionization is used for the analysis of biomolecules such as peptides and proteins.

Answer 29

Time of Flight (MALDI)

Question 30

are widely used for measuring drugs of abuse in urine toxicology confirmations. Drugs and metabolites must be extracted from body fluids

Answer 30

GC/MS