Direct Pcr Testing
Direct Pcr Testing - Related Videos
12:30
Testing Visual Sensitivity to the Speed and Direction of Motion in Lizards
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Cited by 2 •
2006
Testing visual sensitivity in lizards using an operant conditioning paradigm that employs video playback of random-dot kinematograms and computer-generated invertebrates.
10:41
Wild-type Blocking PCR Combined with Direct Sequencing as a Highly Sensitive Method for Detection of Low-Frequency Somatic Mutations
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Cited by 5 •
2017
Wild-type blocking PCR followed by direct sequencing offers a highly sensitive method of detection for low frequency somatic mutations in a variety of sample types.
03:41
Agarose Gel Electrophoresis of DNA Amplicons Post PCR: A Method to Analyze Products of Multiplex PCR and Evaluate PCR Reaction Success
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2025
In this video, we demonstrate the separation of bacterial PCR-amplified DNA using agarose gel electrophoresis. Agarose gel functions as a molecular sieve, enabling the negatively-charged DNA to migrate based upon their size under an applied electric field.
08:51
Genotyping of Staphylococcus aureus by Ribosomal Spacer PCR (RS-PCR)
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Cited by 9 •
2016
Here, ribosomal spacer PCR (RS-PCR) is used together with a miniaturized electrophoresis system as a fast and high resolution method for genotyping S. aureus at moderate costs allowing a high throughput.
13:27
PCR: The Polymerase Chain Reaction
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2023
The polymerase chain reaction, or PCR, is a technique used to amplify DNA through thermocycling – cyles of temperature changes at fixed time intervals. Using a thermostable DNA polymerase, PCR can create numerous copies of DNA from DNA building blocks called dNTPs. There are three steps in PCR: denaturation, annealing, and elongation. Denaturation is the first step in the cycle and causes the DNA to melt by disrupting hydrogen bonds between the bases resulting in single-stranded DNA. Annealing...
FAQs
Inhibitor-tolerant reagents are central because biological samples can carry substances that interfere with DNA amplification. These reagents help the thermostable polymerase remain effective despite that sample background, allowing the reaction to proceed without purification. Their role is especially important when working with tissue, environmental material, or other samples in which unwanted components accompany the target DNA.
Primers determine which DNA region is copied, giving the assay its sequence-level selectivity. The thermostable polymerase extends those primers using nucleotides during repeated temperature cycles, so DNA associated with the selected primer targets is preferentially amplified. This division of roles links primer selection to what the test can detect and polymerase activity to whether amplification proceeds.
Compared with conventional PCR workflows, direct PCR removes the separate purification step, reducing hands-on processing and shortening the path from sample to amplification. The reaction must therefore tolerate substances carried over from the biological material. Direct formats are particularly useful when speed and sample conservation matter, provided the specialized reagents can withstand potential inhibition.
To set up the assay, the biological sample is added to a reaction containing primers, thermostable DNA polymerase, nucleotides, and buffer. The mixture then undergoes repeated denaturation, primer annealing, and extension cycles. Specialized reagents may be included to counter sample-derived inhibitors, helping the selected DNA sequence amplify without a separate purification stage.
The approach supports several biology workflows, including rapid genotyping, pathogen detection, colony screening, and analysis of tissue or environmental samples. These uses differ in their biological questions, but all rely on amplifying a selected DNA sequence directly from available material. The simplified workflow is valuable when researchers need results quickly or want to reduce processing of the original sample.
Because it can proceed without a separate DNA purification step, the method reduces transfers and processing before amplification. That matters when the starting material is limited, as in some tissue or environmental samples. Less handling can also simplify screening workflows, including colony analysis, while conserving the available material for the direct amplification reaction.