Immunoassays and automated procedures Flashcards
what type of immunoassay requires washing?
heterogeneous
what type of immunoassay does not require washing?
homogeneous
what are the 3 types of labels applied in immunoassays?
enzyme immunoassay
chemiluminescence
fluorescent substances
what is chemiluminescene?
refers to light emission
what is enzyme immunoassay? (ELISA or EIA)
designed to detect antigens or antibodies producing and enzyme triggered color change
what are catalytic properties of enzymes used for?
detects and quantitates immunologic reactions
what is a non competitive enzyme immunoassay?
amount of color is proportional to the amount of antibody in the serum
what is a competitive enzyme immunoassay?
amount of color is inversely proportional to the amount of antibody serum
what is a capture enzyme immunoassay?
designed to detect specific type of antibody such as igM or IgG, CMV IgM, rubella IgM, or Toxoplasma IgM
Chemiluminescent labels are used to detect what?
proteins
viruses
oligonucleotides
genomic nucleic acid sequences
what 2 formats are used for chemiluminescene labels?
competitive and sandwich immunoassays
What are the five major groups of chemiluminescent labels?
Luminol
Acridinium esters
Peroxyoxalates
Dioxetanes
Tris rutenium
(LAP Dance Tonight)
what kind of markers are used with Immunofluorescence?
enzyme substrate markers
what enzyme labels are used with Immunofluorescence?
HRP and ALP
What is direct Immunofluorescent assay?
a conjugated antibody used to detect antigen-antibody reactions at a microscope level
what is inhibition Immunofluorescent assay used for?
used to confirm the specificity of the FA technique
What is SQUID technology use?
super paramagnetic particles
what does SQUID technology detect
listeria monocytogenes
How does nepelometry work?
the amount of cloudiness or turbidity is measured photmetrically
what is nephelometry used to measure?
complement components
immune complexes
presence of a variety of antibodies
what is nephelometry based on?
a reaction between the protein and a specific antiserum
what is the heidelberger curve
the relationship between the quality of antigen and the measuring signal at a constant antibody concentration
what is flow cell cytometry
stained cells pass through laser beam
what is polymerase chain reaction?
in vitro method that amplifies low levels of specific deoxyribonucleic acid
what are the three cycles of PCR?
DNA denaturation
Primer annealing
Extension of primed dna sequence
what is the disadvantage of PCR?
it is prone to producing false positives because it’s highly sensitive
what are the important applications of PCR?
amplification of dna
identification of target sequence
synthesis of a labeled antisense probe
what can pcr lead to?
detection of gene mutations that signify early development of cancer.
what is associated with mutations of the gene that encodes for the low density lipoprotein receptor?
coronary artery disease
how does gel electrophoresis work?
dna has a net negative charge and will migrate towards the anode
molecular testing has what advantages?
faster turnaround time
smaller required sample volumes
increased specificity and sensitivity
what is considered the gold standard for molecular methods?
DNA sequencing
how does DNA sequencing work?
it displays the exact nucleotide or base sequence of a fragment of the targeted DNA
what is the most frequently used method?
sanger method
Southern Blot
specimen DNA
ssDNA
sickle cell anemia
Northern Blot
mRNA
Western Blot
Proteins
What is nucleic acid sequence base amplification used for?
detection and quantification
