Laboratory Techniques For Biologists: Antibody Techniques and Microscopy

Question 1

Immunoassay techniques

Answer 1

Immunoassay techniques are used to detect and identify specific proteins

These techniques use stocks of antibodies with the same specificity, known as monoclonal antibodies

An antibody specific to the protein antigen is linked to a chemical ‘label’

The ‘label’ is often a reporter enzyme producing a colour change, but chemiluminescence, fluorescence and other
reporters can be used.

In some cases the assay uses a specific antigen to detect the presence of antibodies.

Question 2

Western blotting

Answer 2

Western blotting is a technique, used after SDS–PAGE electrophoresis

The separated proteins from the gel are transferred (blotted) onto a solid medium

The proteins can be identified using specific antibodies that have reporter enzymes attached

Question 3

Microscopy

Answer 3

Bright-field microscopy is commonly used to observe whole organisms, parts of organisms, thin sections of dissected tissue or individual cells

Fluorescence microscopy uses specific fluorescent labels to bind to and visualise certain molecules or structures within cells or tissues