Immunochromatography Lab Flashcards
What is another name used to describe the immunochromatography lab test?
Lateral Flow Test
What is the main principal behind the lateral flow test?
antibody-antigen complex formation
What is chromatography?
the flow of liquid
What is the most frequently used immunological lab test?
immunochromatography test
State examples of immunochromatography lab tests.
- SARS-CoV2
- pregnancy tests
What are the 4 useful characteristics of immunochromatography lab tests?
- very fast (5-10 minutes) (like immunoagglutination just much more easier to spot)
- very accurate, quick result presentation, either positive of renagive result. no misinterpretation
- cheap (more expressive than immunodiffusion)
- not a lot of skill needed to preform the test.
Explain the basis about how the immunochromatography test works.
- immonochromatigraphy test: porous material (looks like paper): liquid sample must move from one end to another end of the strip
- molecules encounter different zones: different reactions occur
- can test any liquid sample.
- dilute sample, make it less viscous, make it travel through the material easier
- can test for both antigen and antibody
What type of sample can be tested via immunochromatography?
any liquid sample (must be diluted previously)
What do immunochromatography tests test for?
both antibody and antigens
What are the zones present in immunochromatography?
Zone 1: Conjugated-Antibody Adhesion
Zone 2: T-zone
Zone 3: C-zone
Explain zone 1 of the immunochromatography test.
- ZONE 1: ANTIBODY PRODUCTION (specific to antigen on the pathogen) conjugated antibody - any antibody having something attached to it ; contains material which allows it to give a signal –> NANOPARTICLES (very small particles eg. gold or silica particles, if nanoparticles are concentrated in a small area–> group cluster together producing a certain colour signal visible to the naked eye. (gold=red ; silicate=blue)
- after antibody antigen complex is formed, it is brought further on via the flow of the liquid sample.
- free antibodies, move easily with the liquid
- conjugated (with nanoparticles)
What is the conjugated particle in immunochromatography?
nanoparticle
Explain zone 2 of the immunochromatography test.
ZONE 2: T ZONE
- population of antibodies specific to the antigen
- immobilized antibodies (onto the surface of the strip) remain in place when liquid flows through them
- not conjugated. (no nanoparticles attached to them)
- antibody antigen complex is anchored in the T zone via THE ANTIGEN!! (antigen has many domains where the antibodies can bind to; multiple antibodies can bind to a single antigen)
- interesting formation builds: antibody-antigen-antibody(conjugated) SANDWICH COMPLEX
- immobilized antibodies are closely linked together–> antibody-nanoparticles+antigen are close together–> colour seen
Explain zone 3 of the immunochromatography test.
ZONE 3: C ZONE: CONTROL ZONE
- antibody zone
- immobilized antibodies
- not specific to the antigen,
- specific to the antibodies encountered in the first zone
- free antibodies (not bound by antigens) are carried through the fluid, NIT IMMOBILIZED in T zone–> no antigen to join to. –> carries to control zone, nanoparticles show colour
- antibody-antibody formation–> colour seen
What is the sign for a positive and negative immunochromatography test?
2 lines: positive
1 line: negative
Which line in the immunochromatography test is always control?
2nd line
Explain what occurs at the different immunochromatography test zones when testing for an antibody instead of antigen.
ZONE 1: antibody-conjugated antibody (specific to antibody)
ZONE 2: t zone: antibody-conjugated antibody-antibody (still SANDWICH)
ZONE 3: c zone: free antibodies interact with control antibodies
only antibodies are immobilized!
