Polymerase Chain Reaction (PCR)

In Molecular Biology, PCR (polymerase chain reaction) is used to amplify pieces of DNA through a number of cycles into millions of copies of the DNA sequence.

The technique relies on Thermal Cycling, which consists of a heating and cooling sequence to separate the DNA double helix into single strands for amplification with a polymerase enzyme. As the cycle continues the strands of DNA formed are then used to make copies so the process is exponential.

The polymerase enzyme used is a heat-stable DNA polymerase (Taq Polymerase) an enzyme that originated from the bacterium Thermus Aquaticus.

It assembles a new DNA strand from nucleotides (DNA building blocks) and oligonucleotides (DNA primers). What are the PCR steps:

• Denature DNA 94-96 oC
• Anneal Primers 50-65 oC
• Extend Primers 72 oC
• Go to Second cycle

After this the sample is normally centrifuged to collect the DNA pellet.

With over 100 years of centrifuge manufacturing experience, Hettich offers a number of centrifuge packages to accomplish this task.

Whether its PCR microliter centrifuge tubes or PCR strips, Hettich can spin down small or large sample sizes such as our 48-place (1158-L) microliter centrifuge tube rotor for our Mikro 220 centrifuge, which spins at 21,255 RPM/18,845 RCF.

If you are using new technologies such as the TaqMan® PCR cards from Applied Biosystems® we also have custom adapters for these cards approved by the card manufacturer for reliability. The Hettich Rotanta 460 centrifuge not only satisfies this application, however it offers many other rotors, buckets and adapters for numerous standard and specialty application.

Applied Biosystems® TaqMan® is a registered trademark of Life Technologies™