Electrophoresis Flashcards
→ A molecule that contains both acidic & basic groups (amino acid = carboxyl & amine groups)
AMPHOLYTE
→ Rate of migration of a charged solute in an electric field
ELECTROPHORETIC MOBILITY
→ Preferential movement of water in 1 direction through electrophoresis medium due to selective binding of 1 type of charge on the surface of the medium
ENDOSMOSIS
a record that consists of the separated components of a mixture produced by electrophoresis in a supporting medium
ELECTROPHORETOGRAM
: type of electrophoresis limited to migration of small ions
IONTOPHORESIS
: type of electrophoresis usually used for migration of macromolecules
ZONE ELECTROPHORESIS
The movement of electrically charged compounds in a medium resulting to their separations based on their electrical charges when an electric current is applied
Electrophoresis
Macromolecules found in:
-proteins in serum
-urine
-cerebrospinal fluid (CSF)
-erythrocytes and tissue and,
-other biologic body fluids
ELECTRODES:
a. Cathode —- negatively charged
b. Anode —- positively charged
Factors Affecting Rate of Migration
Net electric charge of the molecule
Size and shape of the molecule
Strength of electrical field
Temperature of operation
Properties of Supporting Medium
Components of Electrophoresis
- Driving force (electrical power)
- Support Medium
- Buffer
- Sample
- Detecting System
In electrophoresis, heat is produced when_____ flows through a medium that has_____, resulting in an increase in thermal agitation of the dissolved solute (ions) and leading to a decrease in resistance and an increase in current.
Driving force (Electrical Power)
current; resistance
Supporting Medium
Cellulose acetate
Agarose gel
Polyacrylamide gel
Cellulose is acetylated to form cellulose acetate by treating it with ______
a dry, brittle film composed of about___ air space
homogenous medium with uniform pore size and does not absorb the protein
Cellulose acetate
acetic anhydride; 80%
A highly purified uncharged polysaccharide derived from agar requires small amounts of sample (approximately 2 mL) it does not bind protein and, therefore, migration is not affected
Agarose gel
referred to as ____
layers of gel with different pore sizes are used
separates serum proteins into___ or more fractions rather than the usual five fractions separated by cellulose acetate or agarose
Polyacrylamide gel; PAGE
20
-separates proteins on the basis of surface charge and molecular size, as does polyacrylamide gel.
-not widely used because of technical difficulty in preparing the gel
Starch
o Polysaccharide extracted from sea weed.
o Gel casted horizontally
Agarose
o Non-toxic.
o Separate large molecules
Agarose
o Commonly used for DNA separations.
o Staining can be done before or pouring the gel.
Agarose
o Cross-linked polymer of acrylamide.
o Gel casted vertically.
Polyacrylamide Gel
o Potent neuro-toxic.
o Separate small molecules.
Polyacrylamide Gel