Molecular Diagnostics Signal & Probe Amplification Flashcards
Major difference between Target and Signal & Probe amplification techniques
In signal and probe amplification target sequences do NOT increase.
2 methods of signal amplification
-Branched DNA Amplification (bDNA)
-Hybrid Capture Assays
Signal amplification method that is a solid-phase method; sandwich hybridization assay
Branched DNA Amplification (bDNA)
Branched DNA Amplification measures DNA (or RNA) by measuring the amount of ________ produced
Light
TRUE or FALSE:
In bDNA, the amount of light produced is inversely proportionate to the amount of target in the sample.
FALSE - directly proportionate
Signal Amplification method that measure nucleic acid molecules by boosting a reporter signal and uses a 96-well microplate format
bDNA
Substrate used in bDNA
Dioxetane (generates the chemiluminescent signal)
Common uses for bDNA (3)
-HCV testing
-Hepatitis B testing
-HIV-1 testing
bDNA or Hybrid Capture Assays?:
Advantages include:
-Less risk of carry-over contamination
-Increased specificity
-Detection of multiple genotypes of one virus
-Qualitative and quantitative uses
bDNA
Signal Amplification method that is similar to antibody capture
Hybrid-Capture Assays
Substrate used in Hybrid-Capture Assays
Alkaline phosphatase
Common uses of Hybrid-Capture Assays (3)
-HPV (Human Papilloma Virus)
-CMV (Cytomegalovirus)
-HSV (Herpes Simplex Virus)
bDNA or Hybrid Capture Assays?:
Advantages include:
-Quantitative
-Large numbers of specimens can easily be tested
-No special equipment required
-Turnaround time ~3.5 hours
Hybrid-Capture Assays
2 probe amplification methods
-Ligase Chain Reaction (LCR)
-Strand Displacement Amplification (SDA)
Probe Amplification method that is similar to PCR
Ligase Chain Reaction
