CLB 456 – Clinical Chemistry
Instructions : Please write or type your answers directly into this worksheet.
1. Describe the radioimmunoassay (RIA) method with respect to the following:
a. What is the purpose of adding a radioactive label to either the antigen or antibody in this type of assay? (0.5 points)
b. Briefly describe the two types of radiation used in the clinical lab. (0.5 points)
2. Horseradish peroxidase (HRP), alkaline phosphatase (ALP), and glucose-7-phosphate dehydrogenase are enzymes used in immunochemical methods of detection in the clinical lab.
a. What the name of this immunologic method? (0.25 points)
b. What is the purpose of adding an enzyme to the antigen or antibody? (0.5 points)
c. List the three types of products that result from this method. (0.25 points)
3. Describe the radial immunodiffusion method with respect to the following:
a. What type of media (liquid, solid agar etc.) is used? (0.25 points)
b. Which component of the test contains the antibody and which contains the antigen? (0.25 points)
c. Briefly explain (2-3 sentences) the principle upon which the test operates? (0.5 points)
d. What do positive results look like? (0.25 points)
4. Immunonephelometry and turbidimetry are used as immunochemical methods in specific types of reactions.
a. In what reaction phase (solid, liquid, or gas) is the antigen-antibody complex formed when immuonephelometry and turbidimetry are used? (0.25 points)
b. Why is it important to check verify that reagents and sera are free of light-scattering particles? (0.5 points)
c. What is being measured in turbidimetry when antigen and antibody are combined? (0.5 points)
d. In automated immunonephelometric assays, what is the advantage of having automated sample dilutions made? (0.5 points)