Page 159 - MNU microbiology theoritical 2025

General Microbiology & Immunology (PM 401) Second level Semester 4 2024/2025

• Ouchterlony technique can be done in a Petri dish Antigen and antibody

solutions are placed into separate wells cut in the gel.

• These solutions will gradually diffuse outward in the gel, meeting between

the wells. If the antibody molecules recognize the antigen, they will form

antigen antibody complexes, resulting in a line of precipitation at the zone

of optimal proportions.

II. Immunoelectrophoresis

• In immunoelectrophoresis a complex mixture of antigens is placed in a well

punched out of an agar gel

• The antigens are electrophoresed so that the antigens are separated according

to their charge.

• After electrophoresis a trough is cut in the gel and antibodies are added.

• As the antibodies diffuse into the agar, precipitin lines are produced in the

equivalence zone when an Ag/Ab reaction occurs

• This test is commonly used for the analysis of components in a patient’s serum.

Serum is placed in the well and antibody to whole serum in the trough. By

comparisons to normal serum one can determine whether there are deficiencies

General Microbiology & Immunology (PM 401) theoretical handbook Page 148