analytical techniques Flashcards
(14 cards)
What does a weak blood card reaction mean?
Mean that there isn’t enough epitope reaction
What is a monoclonal antibody?
Plasma cell is a clone and produces one antibody
What is a polyclonal response?
Most antigens have multiple complex molecules requiring a polyclonal response
Explain the two key points of antigen-antibody interaction methods of detection
Antibody-antigen interactions occur with diff strengths
They are reversible
What are immunodiffusion techniques dependent on?
On diffusion of antigens and antibodies from wells cut into an agarose gel
What are agglutination techniques?
Technique where antibodies are mixed with cells
Explain immunoassays
Signal detection
Separation of bound and unbound reactants
What are the formats of immunoassays?
Direct: antibody specific to antigen
Indirect: antibody specific to antigen (unlabelled), second anti-immunoglobulin antibody is label
What is ELISA?
Enzyme-linked immunosorbent assay
Used to detect, quantify antibodies, antigens, proteins
Unknown antigens are attached to a solid phase
Explain a sandwich ELISA
Known antigen is bound to wells
Indirect method
Diluted serum contains unknown [] of analyte are added to wells
2nd antibody added which binds to immobilised analyte
What is indirect immunofluorescence?
Technique used to detect auto-antibodies
What is signal enhancement?
Increased number of enzyme molecules bound to target antigen
What does electrophoresis describe?
Migration of a charged particle under influence of an electric field
What happens during electrophoresis?
Biomolecules exist in solution as charged species
Ions that differ in charge/mass will move at diff rates
