Enzyme Immunoassays: Comparing Enzymes and Conjugation

Study Notes

Enzyme Immunoassays

Enzyme immunoassays are a type of bioanalytical technique used to detect and quantify the presence of a specific analyte (e.g., protein, hormone, or antibody) in a sample
The technique involves the use of an enzyme as a label, which catalyzes a chemical reaction to produce a detectable signal (e.g., colorimetric, fluorescent, or chemiluminescent)

Enzyme Options for Conjugation

Horseradish peroxidase (HRP) is a commonly used enzyme in enzyme immunoassays due to its high catalytic activity, stability, and ease of conjugation to antibodies
Alkaline phosphatase (AP) is another popular enzyme option, offering high sensitivity and stability, as well as the ability to be used with a variety of substrates
ß-Galactosidase is a bacterial enzyme that can be used as an alternative to HRP and AP, offering higher sensitivity and improved stability
Glucose oxidase and glucose-6-phosphate dehydrogenase are other enzyme options, although less commonly used due to their lower activities and stabilities

Conjugation of Enzymes

Enzyme-antibody conjugation is typically achieved through covalent bonding using cross-linking reagents (e.g., glutaraldehyde, periodate, or carbodiimide)
The conjugation process requires careful optimization to ensure high yields, stability, and functionality of the resulting enzyme-antibody complex
Factors influencing conjugation efficiency include enzyme and antibody concentrations, reaction pH, temperature, and time

Description

Test your knowledge on enzyme immunoassays, including the comparison of enzymes available and the conjugation of enzymes. Learn about the different enzymes used and their conjugation methods. Improve your understanding of this important laboratory technique.